At NL2, where the
rake is huge, many people defend a
3-bet or fold strategy. If you apply this simplified strategy, JJ surely would be a hand to play and, consequently, 3-bet. For higher stakes, GTO will usually recommend
flatting pre-flop mostly (sometimes only) from the button (or, of course, to defend the biig-blind), with rare exceptions. Take some GTO Wizard ranges and you will notice that at HJ we never flat, we only 3-bet. But again, this is GTO. You could flat if you know what you are doing vs. some specific player to exploit them.
My experience: JJ still is a good hand to 3-bet with at NL2, and that's what I would recommend, but I am probably folding to a 4-bet from UTG. If you somehow flat the 4-bet, you would be almost always vs. QQ+ AK, because that's what the average player in NL2 4-bets with. I don't think people 4-bet TT often, even at NL2. You will almost never find someone who 4-bet light knowing what they are doing. You are a 2:1 dog vs. this range.
From a GTO perspective, this JJ fold would be a crime, but GTO considers that UTG still has a 4-bet light range with
hands like AJs, A5s and 76s!
Therefore, unless you have a specific note on the opponent that he is a maniac, at NL2 you should fold to this 4-bet to avoid trouble: if they made it around $0.50 to $0.60 instead of shoving, you have a very difficult time playing post-flop vs. the average nitty range from UTG at NL2. If board comes low, you will still lose a lot to overpairs. And now that he 4-bet shoves like this, only the fold is a good option, NL2 pool will do this with QQ+ AK only, that's for sure (unless he is a maniac, but there's no way to know).
