Far from as bad as people claim it to be. It's definitely worth playing if you like action games at least. It's a rather consistent experience throughout all campaigns, but they all go through different struggles.
Leon/Helena:
Definitely the worst campaign and unfortunately the slowest of them. The beginning is a major slog due to how many sections you're forced to walk through while doing essentially nothing. It does however get pretty fun and cool once you end up in the city. The people that enjoy this campaign seem to mostly be doing it because it's the most similar to the original RE format, but I don't think it really excuses how boring it is. It really doesn't fit the more action oriented playstyle of this game either. What they did to Deborah was also unnecessary. Do they have to make everything horny? Absolutely distasteful.
Chris/Piers:
People tend to compare this one to CoD which makes sense due to it leaning more into the military fantasy. It's not so much about the monsters in this campaign, but rather the internal struggles of Chris who keeps getting his teammates picked off one by one while trying to pursue his goal. It's pretty fun and probably the best campaign in this game.
Jake/Sherry:
A bit of a mixed bag, but overall a pretty solid experience. It feels like this campaign makes the least sense, at least chronologically since it spans over at least 6 months while taking place at the same time as the other campaigns which seem to take place in less than a week. I don't really like the dynamic between Jake and Sherry since it feels like they were there just to force a couple into the game and have somewhat of a return of the fan favorite from the previous two mainline games Wesker. As their own characters I like them however. The snow area was way too large and there wasn't really any point in actually fighting anything there. Somewhat comparable to RE3 due to the giant monster that follows you throughout the game, but RE3 is more fo a horror game.
Ada:
Both the easiest and the hardest campaign. The difficulty comes from being a solo player experience (you can coop, but it's meant to be played solo) that crams you into tight spaces in a game where mobility is a big factor. This is however mostly just an issue in the first chapter since everything is such a breeze throughout the rest of the game. For the most part you'll be acting like somewhat of a sniper that helps the other characters out. They can however not die so for the most part you can just wait for the AI to do its job. Whenever you're truly playing alone however, stealth is possible and there aren't that many enemies so it's not that difficult anyway. Her campaign is what ties everything together, kind of. It's just not that interesting though and feels more like a bonus mode.
This may not be a good RE game, but it's a good action game. The controls can feel a little clunky when you want to do tighter movement and the aiming feels a bit off at times. It feels like they added a bunch of fan service for no reason which at best was pointless or distracting and at worst distasteful. It's however not that big of a deal unless you play it around your parents or something. This game is probably better as a coop experience, but it's not bad alone either. I'd recommend getting it one sale, but it's relatively cheap normally.