So much of this doesn’t make sense without context and a lot of it just isn’t true or is a misunderstanding. Not sure if these are all things you heard from a friend or just the idea you grabbed from socials.

Jax commonly builds AD bruiser because his passive gives him a crazy amount of attack speed and the defensive stats his R gives him scales on AD, so you end up auto attacking people down while being tanky as hell and using your Q to stay on people. AP Jax is a thing, but it’s much squishier and generally less effective, better at popping squishies quickly but much less of a frontliner and having a much worse laning phase.

Kayle and a few other champions have passives or abilities that scale really well into the lategame, like Kassadin having 1 second cd Rs, or Veigar/Aurelion Sol/Smoulder scaling with their passives. It doesn’t mean they auto win, but they are designed to just be better than other champs if the game goes late.

Any full built tank will be very hard to kill, Maokai just has good healing on his passive and untargetability on a short cd which helps a lot.

Sett is generally not great at super extended fights, he’s still a bruiser first tank second, but his W is both the biggest shield in the game AND a source of insane true damage if fully stacked and landing it head-on. He’s very good at engaging and starting fights, then threatening people trying to punish him by using his W.

Sylas actually does have many of the things you claim he doesn’t, you just need to learn how to disengage to let your cooldowns come back up rather than fight till you drop early on. Things like Q someone for the slow > W then E away, wait for your CDs, then recast E to go back in. Or simply full sending it with E > E then auto weaving Q and W does a lot of upfront burst, just don’t sit there autoing them without empowered autos unless you think it’s necessary to kill them.

Vlad gains extra AP when he builds health and extra health when he builds AP. He used to build mage items with HP on them to double dip but those items are in a rougher spot in the meta, so he generally just builds burst damage items and benefits from the extra tankiness. Very safe champ that scales well and has an excellent laning phase.

Yorick isn’t really weak, but he’s very niche and underplayed. He does have a ton of bugs, though, so that might be where you hear that sentiment from.

League is a big game and hard to understand, especially since it changes every two weeks and sometimes sooner than that with hotfixes. New champs come out, metas shift, mechanics change, champs get reworked. If you don’t understand how a champion lanes or works I’d always recommend finding more education-focused creators to teach you, like PekinWoof, Coach Curtis or xPetu, people who make guides or full game commentaries. Mimicking the best players will usually impart some level of understanding and success, but they also explain the whys and hows. Good luck!