Keeping old content relevant and tomestones

[Jeeqbit]

I feel like "They have to" isn't really true since you can beat any savage starting with your crafted gear, it's just a way to get extra gear and extra rewards for other people down the line.

I mean, that's your opinion. From Yoshi-P's perspective and the perspective of many players, chasing rewards such as mounts is a big deal and a big motivator. If the only way to get a mount is to do it Minimum Item Level and it can't be bought with gil, then collectors HAVE to do it even though they already did it years ago. Whereas if it can be bought with gil, they have a choice.