If you watch Gold's film breakdown, it goes into some of what I'm talking about.
The 3-4 scheme requires more responsibility out of the outside edge/backer, and more importantly it requires different alignments/positioning. Taylor's out wider, and going against RT's 90% of the time, which is usually the best lineman on every line in the NFL.
Maybe there is something to what you're saying, but none of it is provable. Character issues? Eh, hard to believe that when he's balled out for two years prior, and is in a contract year wanting to get paid.
IMO far more about scheme, depth help, and small things that are frustrating him like 3-4 responsibilities and positioning, like Gold's YT video shows.
Well, it's not really accurate to say the RT is the best lineman. The LT, since more QBs are right handed, is typically the best pass blocker, the RT the best run blocker, but I'm pretty sure the highest paid tackles on average in the NFL are still LTs. He's doing poorly in both setting the edge and pass rushing, though, so that's kind of moot.
It does sound like the fact that he's starting wider on most plays (since teams typically line up the TE or slot receiver on that side) is affecting him, though, based on Gold's video, so I do agree that the 3-4 is probably hurting him.
Gold pointed out some technique issues as well, but I feel like some of those might be related to starting wider as well. He mentioned that it's his steps aren't as purposeful, and I feel like maybe he just doesn't have a good feel for how many steps he needs to take from the wider spot on the line?
At any rate, I'm pretty sure his lack of production is playing a role in why Bruce Irvin is being brought in.