Perhaps, but Guitar Tab is one of the great equalizers of the internet - proper notation has typically cost money to access a copy, whereas Tab could spread in .txt format, small sizes, etc. Sure, they could be off or need the song to play along with, but that's the trade-off. Lastly, though it's a personal opinion, Guitar and "proper notation" are really only needed in the same sentence when playing Classical/Orchestra, Real Jazz, or as a Pro Studio Session Musician[1] - as in, very small, elite group of players. Most will get by just growing along with the instrument over the years, for which Tab helps a lot.
[1] Great studio guitarist Glen Campbell supposedly couldn't read music at all, just went along with what he heard and made it work; Tommy Tedesco by comparison could read sheet music upside down.
Ya, plenty of highly successful musicians and "composers" can't/couldn't read music, Paul McCartney being one of the most famous.
Joni Mitchell apparently didn't even use regular tab notation. She'd detune her guitar and annotate the relative pitch shift per string, e.g. D-2 G+1, etc or similar.
I agree, I just feel like it ends up as a crutch for a lot of musicians. For example, it isn't very specific in terms of rhythm so you get a lot of beginners who see that part of music as loose or unimportant.
But of course, up to a point, lowering barriers is always a good thing for beginners.
Depending on the style of tablature used, you can convey rhythm, and more. I'd say it can actually get more specific than staff notation when you allow for guitar specific notation, like all the different types of legato capable, harmonics, and specifying which string to play a note one (it makes a subtle difference).
Here's a screenshot I took of a random song in TuxGuitar (a GNU licensed tablature editor/viewer). You can see the rhythm fairly clearly, as well as the difference between pull-offs and slides.
I disagree; guitar has multiple fingerings for each note or chord and it's not necessarily clear which one will be the simplest to use when given regular staff notation.
There's a huge jump in the complexity of how you need to reason about translating the music to the instrument with staff notation. Tabs solve this by explicitly telling the musician what fingering to use.
Guitar players should still learn to read music because it's useful, but anyone who wants a guitarist to play their music (especially by sight) should use a notation similar to tabs, but with rhythm indicated as well. Good software to convert between the two could be generally useful, but I imagine there is a bit of nuance to what fingerings sound the best.
Early lute music was mostly written in tablature FWIW. A lot of the renaissance repertoire is still published that way. It uses letters rather than numbers to represent the frets, which takes getting used to, and puts separate timing marks above the staff.
[1] Great studio guitarist Glen Campbell supposedly couldn't read music at all, just went along with what he heard and made it work; Tommy Tedesco by comparison could read sheet music upside down.