hi guys. I am wondering why many players 3bet with their linear range at late position nowadays.
For example, when hero has 77 and is on BTN and UTG open raise 3bb, standard play is just call and see postflop. However, when BTN opens, BB 3bet with 77.
I don't want to go too deep with pokersnowie range but this is suggestion of snowie 3bet range from BB 3bet range vs BTN open;
55+,ATs+,A4s-A5s,KJs+,QJs,JTs,T9s,AQo+,KQo

From my perspective, medium strength hands are much harder to play in big pot. They are just good for call preflop and see the postflop, but snowie and other players 3bet with them. IMO, there are plenty of good hands to 3 bet bluff and play in big pot, such as Q5s. They also have blockers, so it can increases the possibility of villain fold.
If BB 3 bet with 55-88, is that value raise? or bluff? Neither of them.

Can anybody explain why we should 3 bet with linear range at late position?