Depends on your focus.

In terms of collecting and raising your units, verily. This game runs on a shards system (which are farmable, with very few exceptions), so dupes are pretty much just a collateral instead of something to pull towards.

In terms of skins though, this is pretty much their main source of income. You can still get free skins and a limited amount of free skin currencies.

TLDR; Basically, yes.

Pretty much vanity items only, nothing gameplay related.

Given how viable most, if not all, launch dolls are to this day, your waifu/husbando.