You're being extremely biased. Their kits do different things are have strengths and weaknesses in different areas. Olaf's and Tryndamere's "lifesteal" function much differently. First, Trydamere doesn't even have lifesteal. He has a heal on his Q that consumes all his rage. You really don't want to use this in a fight as you sacrifice a large chunk of your damage to do so. Tryndamere's Q is more used as a sustaining tool for in lane and split pushing. In contrast, Olaf's lifesteal is actually very useful in an actual fight.
Running in wrecklessly? Tryndamere has dashes to do that.
Absolutely not. This is something Olaf is waaaaayyyyy better at. If Tryndamere spins in recklessly and gets caught in one CC he's done for. Pretty much means he has to pop ult and pray the enemies let him walk out after its over. Tryndamere doesn't get multiple dashes if he's not hitting anything. Tryndamere is notoriously dogshit for team fighting. Olaf's strength lies in being unstoppable while popping ghost and righteous glory and sticking power on his Q refunds
Q slow? Why do that when you can press w for a point and click slow (sometimes) that you can follow up with dashes?
It's really obvious that you're just being salty as fuck over something at thing point. Do I need to explain the mechanics on picking up Olaf's axes and spam slowing people as opposed to Tryndamere's singe use slow?
Lifestealing out of death? Tryndamere ult.
This isn't even a point. Trydamere doesn't have lifesteal built in. He has a single heal on his Q.