I don't think you need to make too many major adjustments. It sounds like they are not elastic in their approach to your RFI range expanding. If I was BB and had stats that you are raising that often, I am going to 3b you to death (I would expand value slightly and start adding bluffs. I would not expand so much linearly since I hate to get 4b when I 3b something like 77 or 66). But, from the sounds of it, the pool/player is still 3 betting the same way.

If they are not adjusting, I would not change too much really. I would, however, look at how often my 4 bets are working against them and consider adding a few more 4b bluffs here and there.

I would say that good regs are 3-betting quite aggressivly, probably need to get a better tagging scheme going.

It seems nonsensical to open exploitatively wide but then feel the need to defend wider vs 3bets. Presumably the whole reason you opened 55% was because they fold too much/don't 3bet enough so I would defend tighter than GTO.

If they are 3betting too aggressively then don't open 55%...