I don't have any degrees because I couldn't afford college but I took lessons for a relatively long time which taught me how to read sheet plus theory.

do you think I could become a good guitarist just learning by myself?

When my guitar teacher used to get praise for his students he would reply that he didn't do much and it was mostly the student. Somewhat of a humble deflection but there is definitely truth to it. The largest benefit of having a teacher is having someone to help guide you, help motivate you during slumps, and having a scheduled time just for guitar in my experience. The knowledge and technique tips themselves are already out there readily available.

If you just want to play the like the guy in the video, yes I think you could learn to do it by yourself. Nothing in that video appeared exceptionally difficult besides singing while playing *and songwriting. The bar chords will take some time because your fingers will be weak and they will hurt in general due to a lack of calluses in the beginning. You can get really light strings to soften this, that's what I did at the start. Playing a chord on demand is just practice but isn't insanely difficult, I just took it slow and tried to get all my fingers to land at the same time. Hammer ons and pull offs will take time, but what he showed in that video didn't seem too hard. However legato is one of those things that can get really difficult really fast depending on tempo and string switching. *Light strings will also help a lot with bending and vibrato bending isn't really that hard, pitch bending definitely takes more work though.

You probably already know some variation of this from drums but you want to create a fluid, economic, easily repeatable motion for muscle memory that doesn't strain you. That is more or less guitar in a nutshell which is of course easier said than done. When I get back I will add some more to this

This video and this video are two good videos that cover picking that I've been referencing recently. Even if you have no intention of playing that genre or at that speed I think exercises are really good for honing in on reproduceable motions which will still benefit playing different genres or at different tempos. I did figure 6 at 3mins in that video a lot years ago and it really helped me with finger independence. I also used to do a variation where I would alternate pick it as a warmup and practice. Additionally I practiced the first exercise in this video a lot which also helped me a ton. The channels from the first and last video are pretty good too, a lot of guitar teachers post great things online which can create a challenge of remaining focused.

I’m leaning towards finding a teacher but COVID + I’m too unhinged for most guitar teachers

I haven't done them but there are people who offer lessons online. Some of them I think are like in person sessions where you talk but I think with others you can just send a video of yourself playing for them. For what it's worth I have poor social skills and have always been very isolated, but I had a great experience with in person lessons.

All in all yeah I think it'd be doable. Doing it routinely and persisting through the rough patches is key. If you don't have a teacher it's possible to get overwhelmed and constantly sidetracked which can be a problem. To combat boredom you can get an interface and record your own things if you have a good enough computer. You can also use the paulstretch effect from audacity to make ambient soundscapes which is really fun and incredibly easy. Also get a small mirror so you can see yourself play and try playing in the classical position because I vastly improved when I switched because I got shoulder pain.