For me, it's WFB up to and including 5th edition (although I might say 4th, but I can't actually tell the difference), and I guess I'd put 2nd ed 40K there as well. So basically HeroHammer, goblin green bases, and just way, way too many cards and counters and dead trees.
I have soft spots for Guiliman, Corvus, and Magnus, and I love to hate hypocritical Mortarion, but I'm of the opinion that the setting is more interesting with less of them. 30K/Horus Heresy is for people who want to do HeroHammer.
Herohammer was... Not Great™️, so I'm wary of systems that try to be goons and guns while also having big ticket super saiyans running around. Outside of that nothing seems egregiously wrong with it. Model availability is the biggest downside.
I get the feeling 4th was quite herohammer-y, but 5th is VERY Herohammer. I'm guilty of running a Vampire Lord on Zombie Dragon which is 875 points before you buy any vampire abilities or magical items. So you can easily have a single character over 1000pts.
Also worth having the context that White Dwarf really hammered - especially for WFB - to fit your army to its fiction. That also kind of mitigates HeroHammer. Stillmania articles were great to get the spirit of the game. Also at 2000 points, there's only so much you can do if you want 3 characters.
So in practice, in the games I played, I never really encountered HeroHammer in WFB except for when that's what we wanted to play. And inevitably my general would die and my whole army would flee, so eh. 40k didn't have that same kind of cascading morale failure.
Yeah, 4th and 5th were when I started collecting Fantasy and they were definitely 'Herohammer'. I remember it being common to have a few units about 12-16 strong and then loading up on characters with as many magic items as possible and a monstrous mount, if you could
Yes, 4th and 5th ed Fantasy were both huge HeroHammer editions. Slightly related, gotta love that one Lord of Change character from Fantasy's 5th edition that had a 1+ daemonic save (basically an invulnerable save that could be negated with magic).