I know what you mean Black cat. The Internet is the greatest source of MISinformation ever invented.
So I'd say - Yes - you should learn ABOUT scales as part of your music theory study. That's useful because the more you understand how scales work, (either from theory or from experience) the more easily you can see through that swamp of misinformation that's out there and decide for yourself which direction to follow.
As for them being
necessary to learn, there's no need to search the net for that, Kirk is living proof that you don't actually
need scales to be a highly accomplished improviser. Case closed.
As for them being
useful to learn, I think everybody agrees that some of them certainly are. For example I can't see anyone advising not to learn the major scale. But to what extent all the others should be learned/ memorised/ practised is something each guitarist has to decide based on what they intend to do with them.