one of the BIGGEST changes of play time is difficulty setting or "assist options" as they call them these days lol
like a VERY good example is dead cells, theres a crapton of difficulty modification down to outright REMOVING game overs (you respawn at the map you died, rather than start a whole NEW run) to dropping enemies damage to 10%!! TEN PERCENT!! you make the game 10x easier with that ALONE.
so how long does it take for someone with infinite respawn and 10% enemy damage to beat the game? much less than someone who didn't do that, since they have to be much careful and possibly build for defense and health, while on 10% enemy damage you can just glass cannon it all to boss cell 5
Ninja gaiden ragebound has an option to reduce enemy damage also
but it can go to ZERO percent on that game, meaning no damage.
remove knockback, and now you have zero reason to ever die other than your own bad jumping skill.
now me, i'm gonna take LONGER to beat the game, you know why?
cause i'm playing at 50% game speed. i'm too old for this shit LOL
Shinobi art of vengence has similar settings to NG ragebound, but no full invincible (it only goes to 50% enemy damage at lowest) respawn nearby (rather than checkpoint, huge time save) and faster combo fill (you can do a finisher attack earlier, another huge time save)
all i used is the respawn nearby, still makes you fight every enemy again.