Does "liquid electrical tape" actually protect against moisture?

I bought some "Star brite" brand liquid electrical tape. Once dried it doesn't seem to have great adhesion to anything.
You can peel it from a PVC cable jacket or PCB using a finger nail and light pressure. It's much less "sticky" than the adhesive you get on electrical tape.
I could only see it surviving long term if the whole area is protected from mechanical stress.

Electrical tape isn't supposed to be resistant to mechanical stress. It isn't supposed to be exposed to the general public either, just safely contained inside a grounded metal enclosure. What is it that you expect it to survive?

In real world use, does it actually keep moisture out, or is it a placebo?
I would be surprised if something with such poor adhesion could keep moisture out, but I would like to be proven wrong.
I’m reluctant to try wrapping it with some other protective layer in case the sheer stress during the wrapping process causes it to peel away.

Self-amalgamating tape is used, it forms a seal. Other insulating tapes do not seal. The liquid mentioned
seems to be a brush on sealant designed to be waterproof (but not mechanically robust it appears).