Jak 1 is an ok successor the the ps1/n64 era of platformers, yeah. Nothing really special, but its a run romp.
Jak 2 is one of the worst games I've ever played. Like I have no idea what compelled Naughty Dog to end up with such a humongous turd, more so praising it as the future of platformers. Ruined Jak's "character", has a sprawling but entirely soulless GTA style city with nothing to do in it, has tons of escort missions with hard fail states... man I could go on. I fell into a funk where I didn't want to play any more games for a while after beating it cause of how bad it was.
With Sly Cooper, I really really didn't like Sly 2. In addition to the other characters not being fun to play as, the game lasts at least three times as long as it needs to and the "hub" worlds are immense to the point where navigating through them over and over to complete story stuff isnt fun at all, even less so when playing as Murray or Bentley who have like 1/4 of the traversal options Sly has. Like, at one point Sly and Murray get kidnapped and you're forced to play as slow-moving and awful jumping Bentley all across this huge hub city where getting from point A to point B is an exercise in frustration. Sly 1 was infinitely better, imo, with 3 having a better balance between the hub traversal and making the secondary characters more fun to play as. Four goes back to 2's style, but makes the hub worlds way smaller/easier to navigate and circumvents the "shitty party member" issue by making all of them Coopers from different times.
Ratchet games are one of the few PS2 trilogies that are great all the way through. I do have my complaints about them, but they're really nitpicking in the grand scheme of things. Really fun games.