There's literally nothing that's universally liked, taste and people differ too differently. Also add to that when something is praised it leads to some people who actively try to not enjoy themselves or focus on the negatives more than the positives, which I do fully believe the mindset you go into anything will in fact change your personal experience with it.
I love Resident Evil 4, I think is superbly designed for what it's trying to be and paced fantastically, but frankly some people just are not going to like what it's trying to be in the first place.
I think RE4 is REALLY GOOD at what it's aiming to be, it hits with the audience it was aiming for masterfully. But what it was aiming to be was not universal, and that's fine as nothing is universally liked. The reason you see so many people praise RE4 is three main reasons though;
01.) It was one of the game changers in the history of gaming, if you were making a list of the most influential video games ever released, RE4 would be included on it no doubt. Influencers often get a lot of leeway because they created/popularized several new things that changed the industry through being impactful. It's why you, for example, see people regard the original Super Mario Bros for example as one of the best games ever made.
02.) Despite it influencing a lot, there's actually not much that's exactly like RE4. Dead Space and Gears of War both took direct inspiration from it, and some may prefer them for their personal taste, but neither really has that exact charm RE4 has, they have differing charms. Hell, even RE5 despite following RE4's blueprint in ways is quite different due to huge changes in the system to make it co-op focused and quite different level design/atmosphere/pacing and some parts of the game removed and others added from RE4's formula. Frankly there hasn't been a game since RE4 which has strictly felt like RE4 to me, so for people who find the appeal in elements of RE4 it still hasn't been topped in all the areas it excelled it can how it brought them together. That's not to say there's not been any age to the product, I know many are used to modern control schemes so that's usually one of the biggest hurdles, but it's aged relatively fine.
03.) Frankly I can hardly think of any campaign game that has as much consistent variety and pacing quality as RE4. And I think that's part of what's made it stick around so long with such positive reception overall, the game is quite long for the sort of game it is yet it is paced extremely well and utilizes well designed scenarios. Not all scenarios will be to everyone's liking, but there's quite a few in there and all of them bring unique twists to each encounter and it continually builds on itself. There's very few games that have the sort of pacing and variety design that RE4 has, and it even helps against potential frustration having a scaling difficulty as you play, making skilled players get by with harder challenges and yet more potential reward to upgrade themselves in how they see fit, while also letting newbies get into it and not too frustrated.
There's more touches, but frankly it's an example of a game that mastered what it was trying to be, so that's why it's so well regarded. That said, not everyone likes what it was trying to be, and not everyone is happy that RE4 was part of the RE franchise, but that's perfectly fine and even expected really.