Goddammit, now what?

Possible reasons why this happens:
An update was recently released that changed the game for the worse, causing long-time players to change their review.
It's an early access title that's been abandoned by the developer, and is being justifiably review bombed as a result.
It was recently included in a bundle, so there's a lot of new players who weren't interested enough to buy the game on its own, but played it after receiving it in the bundle and were unimpressed. I'd give this one the least weight, because often times those are players who just don't like the genre or went in with too-high expectations for a low budget game.
- In the case of Oblivion Remastered (not the proper one, the Bethesda one) it seems closer to #2. It has very similar reviews to this screenshot. A lot of people were excited and happy to play it, but as time went on people found that the game was actually moderately bugged and has many progress breaking issues that the devs ignore. I'm assuming that Bethesda released this purely to undermine Skyblivion, but it's clear which dev team cares about what they produce. Side note, the absolute scumbags charge £50 for it. A remaster should never be above £20
  
  I really don't know what people expected with oblivion remastered tbh, its a Bethesda title of course it's broken
  
  Side note, the absolute scumbags charge £50
  I was downvoted for pointing this out.
  
  Did that happen? I bought Oblivion Remastered on release day and had minimal problems with it, it's a Bethesda game so some are to be expected. I've run through it twice now and have had a blast.
  
  the game was actually moderately bugged
  Does that mean Bethesda actually fixed 95% of their release bugs?
- You forgot
  An update was recently released that didnt change the game in a way some long-term players wanted, and they're angry they fell for hype from streamers and are taking it out on the devs instead.
  Or, as we recently saw in helldivers
  An update was recently released with a bad translation, and gave players an expectation they could do something that they couldn't, and it became politicized

In addition to what other people already said, without looking at the actual percentages, this could also just be random fluctuation.
Mostly Positive is 70-79%, Mixed is 40-69%. If a game teeters around the 70% mark, it can easily cross the threshold separating the two due to pure chance, in either direction.

I also hate it when changes to the game ruin it. Every time I have seen this happen there were changes to the game for the worse that are easy to confirm by looking at where the decline starts and checking out reviews shortly after.
Adding microtransactions, breaking the game, trying to enforce a 3rd party login requirement 3 months after the game was a massive success...
- trying to enforce a 3rd party login requirement 3 months after the game was a massive success...
  At least got cool cape from executive lobotomy. Fuck sony, FOR DEMOCRACY.
  
  The cape is badass!

any games that are the opposite? that started with terrible reviews then improved a lot?
besides No man sky?
- Cyberpunk

now what?
Don't buy it?
- How do we do that for the timeline itself, though? Can't say it's much different IRL. 😅

Oh shit, this is for Oblivion Remastered 😂
Edit: Before I read the new reviews let me guess... This is because Virtuoso is laying off 300 employees?
Edit 2: I didn't spot a trend, just the typical complaints e.g., entitlement, bugs, greed, boring, people with potatoes.
- people with potatoes.
  Why you gotta do my boy Sam like that? 🥹
  
  Indecision, frankly
  When you're 30 mins into cooking a brace of coneys, if you don't know whether you're boiling or mashing your potatoes, you're kinda negligent. If your fucking plan is to put the spuds in the fucking stew, I think you need to step away from the pot and really take a long hard look at the clown you've become, because that should have happened half a fucking hour ago.

Now you buy it and try it yourself, if you're interested. You can return the game if it's not too your liking after the first hour of play.
- Its 2 hours of play or two weeks from purchase, whatever comes first. Pretty nice actually.
  
  I understand that they can’t let you play indefinitely before returning a game, but I find 2 hours very little to see if you like a game, especially for complex games.
  Other games, like Rimworld or Cities: Skylines need some hours in before they make it obvious that they’re horrendously optimized or have otherwise questionable decisions (like imperfect pathfinding) that will annoy you.

Just buy it and don't play it.
- I'm in this comment and I don't like it.

Bad update or long term issues lasting over various updates. Honestly sounds like oblivion remastered.

...c'est la vie...

Buy, play for a few days, ask for refund within 14 days if don't like
- Only if you play for less than 2 hours though
  
  They will sometimes refund it after the 2 hr playtime, but you have to actually escalate the ticket to get a chance at that refund.