Here we go, I also uninstalled the Microsoft Store App version, and installed the version that "works," for most everyone after I found that the App version has issues. Sadly, this didn't resolve mine.
I should point out that the board download works fine, it's just the libraries that aren't. I was able to get a few installed for my board, but I had to download the ZIP files by hand and use the ZIP installer.
2020-08-27T01:40:07.240Z INFO c.a.u.n.FileDownloaderCache:92 [LibraryManager Update Thread] Cache folder C:\Users\<user name>\AppData\Local\Arduino15\cache
2020-08-27T01:40:07.260Z INFO c.a.u.n.FileDownloaderCache:112 [LibraryManager Update Thread] Number of file already in the cache 4
2020-08-27T01:40:07.278Z INFO c.a.u.n.FileDownloaderCache:149 [LibraryManager Update Thread] Get file cached is expire false, exist true, info FileCached{eTag='4e4f353a7c28cfb3b7ec6dc1f3cf1a17', lastETag='null', remoteURL='https://downloads.arduino.cc/libraries/library_index.json.gz', localPath='C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.gz', md5='MD5:4e4f353a7c28cfb3b7ec6dc1f3cf1a17', createdAt='2020-08-26T18:34:38.343', cacheControl=CacheControl{maxAge=14400, isMustRevalidate=false, isNoCache=false, isNoStore=false}}
2020-08-27T01:40:07.296Z INFO c.a.u.n.FileDownloader:210 [LibraryManager Update Thread] No need to download using cached file: FileCached{eTag='4e4f353a7c28cfb3b7ec6dc1f3cf1a17', lastETag='null', remoteURL='https://downloads.arduino.cc/libraries/library_index.json.gz', localPath='C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.gz', md5='MD5:4e4f353a7c28cfb3b7ec6dc1f3cf1a17', createdAt='2020-08-26T18:34:38.343', cacheControl=CacheControl{maxAge=14400, isMustRevalidate=false, isNoCache=false, isNoStore=false}}
2020-08-27T01:40:07.298Z INFO c.a.u.n.FileDownloader:174 [LibraryManager Update Thread] The file will be taken from the cache Optional[C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.gz]
2020-08-27T01:40:07.415Z INFO c.a.u.n.FileDownloaderCache:149 [LibraryManager Update Thread] Get file cached is expire false, exist true, info FileCached{eTag='7edc149591f7d2b6628d924b506538b0', lastETag='null', remoteURL='https://downloads.arduino.cc/libraries/library_index.json.sig', localPath='C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.sig', md5='MD5:7edc149591f7d2b6628d924b506538b0', createdAt='2020-08-26T18:34:38.672', cacheControl=CacheControl{maxAge=14400, isMustRevalidate=false, isNoCache=false, isNoStore=false}}
2020-08-27T01:40:07.417Z INFO c.a.u.n.FileDownloader:210 [LibraryManager Update Thread] No need to download using cached file: FileCached{eTag='7edc149591f7d2b6628d924b506538b0', lastETag='null', remoteURL='https://downloads.arduino.cc/libraries/library_index.json.sig', localPath='C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.sig', md5='MD5:7edc149591f7d2b6628d924b506538b0', createdAt='2020-08-26T18:34:38.672', cacheControl=CacheControl{maxAge=14400, isMustRevalidate=false, isNoCache=false, isNoStore=false}}
2020-08-27T01:40:07.418Z INFO c.a.u.n.FileDownloader:174 [LibraryManager Update Thread] The file will be taken from the cache Optional[C:\Users\<user name>\AppData\Local\Arduino15\cache\downloads.arduino.cc\libraries\library_index.json.sig]
2020-08-27T01:40:07.584Z INFO c.a.c.DownloadableContributionsDownloader:227 [LibraryManager Update Thread] Signature verified. url=https://downloads.arduino.cc/libraries/library_index.json.sig, signature url=https://downloads.arduino.cc/libraries/library_index.json.sig, file to verify=C:\Users\<user name>\AppData\Local\Temp\library_index.json4690458321942612983.tmp, signature file=C:\Users\<user name>\AppData\Local\Temp\library_index.json.sig4408297769289596138.tmp
2020-08-27T01:40:24.431Z INFO c.a.u.n.FileDownloaderCache:131 [LibraryManager Installer Thread] The cache is not enable.
Nothing jumps out at me here..
Here's where I tried to start the download for the BLE library:
2020-08-27T01:40:24.434Z INFO c.a.u.n.HttpConnectionManager:153 [LibraryManager Installer Thread] Connect to http://downloads.arduino.cc/libraries/github.com/arduino-libraries/ArduinoBLE-1.1.3.zip, method=GET, request id=4525CCF9BD3E430C
2020-08-27T01:40:25.705Z INFO c.a.u.n.HttpConnectionManager:157 [LibraryManager Installer Thread] Request complete URL="http://downloads.arduino.cc/libraries/github.com/arduino-libraries/ArduinoBLE-1.1.3.zip", method=GET, response code=206, request id=4525CCF9BD3E430C, headers={null=[HTTP/1.1 206 Partial Content], Server=[cloudflare], Content-Range=[bytes 0-105157/105158], Last-Modified=[Mon, 29 Jun 2020 09:34:33 GMT], X-Amz-Cf-Id=[karMmR7n90Fnu_HuJhLRyT-OU2pJyt_UCfxaNwEPuJ_49wzG9b5DQw==], Set-Cookie=[__cfduid=d2d3b735908a2d2cf6c29a89657028b151598492426; expires=Sat, 26-Sep-20 01:40:26 GMT; path=/; domain=.arduino.cc; HttpOnly; SameSite=Lax], Content-Length=[105158], Age=[245439], cf-request-id=[04cf2bda930000ed8ba296f200000001], Content-Type=[application/zip], X-Cache=[Miss from cloudfront], CF-Ray=[5c9215a41e65ed8b-SJC], X-Amz-Cf-Pop=[SFO20-C1], Connection=[keep-alive], x-amz-version-id=[xh76u4yUhOEXar4M65Jk5BiE_An2aOe2], Date=[Thu, 27 Aug 2020 01:40:26 GMT], Via=[1.1 88734c1b1a8053ae83daf0f85731c788.cloudfront.net (CloudFront)], x-amz-replication-status=[COMPLETED], CF-Cache-Status=[HIT], Cache-Control=[private, max-age=14400], ETag=["6bfba008afd7ab7baa2f3eb093232fdc"], Vary=[Accept-Encoding], x-amz-request-id=[36D1A0529EE0F66E], alt-svc=[h3-27=":443"; ma=86400, h3-28=":443"; ma=86400, h3-29=":443"; ma=86400], x-amz-id-2=[VELvo+w6zMq+VSAfdzS0ILW8hH0ER2IT8ahTmFgBT0rdehc8L1SwnkpQFY13OEOq7uMp292ehjM=]}
And from here it stops, just dead stop. If I try to close the library window nothing happens, and I have to use Task Manager to kill the instance.