I think bit fields will work just like expected for some time to come,
if only to support legacy code - from the time when memory was expensive.
If you use the bit fields, it just shifts the burden of masking and shifting to the compiler.
It should work on any platform, as the base type for the fields and the combined data is the same.
Sure, there are limitations, but for the above simple dissecting it should work on any platform.
The readability of the bit field variant is much better, and the chance to make an error much lower.