As a game, it's better than 7 in every way. A lot of steps are taken to make the combat has more depth and it's very fun to play.

As a story though... Infinite Wealth tries to juggle too many ideas but failed to have a good followup for most of them. About the only things that is done well is Yamai, Tomi and Chitose.
------SPOILERS AHEAD------
-- It starts building a romantic relationship between Ichiban and Saeko. It would be nice if we get any more scene with those two together other than the very beginning and end of the game. Not to mention the 1 year time skip's only purpose is to make both parties look terrible (especially more so for Saeko) so it's hard to get invested in their romance.
-- For how integral Sasaki's plight is to Ichiban's ideal about reforming yakuzas, the game certainly forgot about him entirely after the first chapters. Putting him on the island is the perfect way to strengthen the team's resolve, but nope, not mentioned at all.
-- Wong Tou got to live after revealing crucial information? Wow that's new and surprising, it's a shame that he does absolutely nothing afterwards and die in the most unceremonious way ever. It would have made zero difference if he was shot right there in the forest as per tradition. The Ganzhe was a whole bunch of nothing in general.
-- Ebina's motivation is actually pretty compelling, calling out the whole "honorable yakuza" bullshit and how they only ruined civillian's lives. Would be nice if he had more presence since the game ignored him the moment we get into Hawaii, and him also being Arakawa's son seemed like some last minute plot twist nonsense that ultimately didn't matter, he could have been anyone who got ruined by Arakawa but I guess we need some more symbolism.
-- The game drew a paralell between Lani and Haruka and how Kiryu felt the need to save Lani like he did before, then it immediately brought Kiryu back to Japan away from Lani and the cult so he couldn't do anything. Lani in general could have just been the necklace considering she is barely a character.
-- Nothing in Gaiden got followed up on besides "So... Hanawa died." And that's it.
-- It's really nice that for the 2nd game as the new protagonist Kiryu got to steal the spotlight. After the split Ichiban's side got nothing interesting, it's a basic JRPG plot with a Yakuza skin to chase after crysta- I mean Lani/the necklace and then you defeat an evil cult, its giant monsters and then a god. Kiryu side got all the memoirs and things that is actually related to the yakuza and the dissolution, you know, why these games are so compelling in the first place?
-- The Eiji moment at the end... it could have worked if, once again, he got literally any more screen time. They made him so comically evil that it's impossible to symphatize with him. Aoki and Ebina was trying to get rid of people they deem as scum, Eiji was trying to help kill an innocent kid and showed no sign of faltering before the very ending. Not to mention there clearly was supposed to be some more scenes with him considering he somehow grew a beard and teleported back to Japan to get shit on.

I could go on for a little bit more but overall, I'm disappointed and I hope they spend a longer time cooking on RGG9.