My main issue with templates is that many of them have zero function; the "has connections to or written by" ones are especially shitty. Look at this garbage:
https://wiki.soyjak.st/index.php?title=Furry&oldid=144112 Let's look at the "oldfags" template for example: you didn't need a giant technicolor box hogging up space at the top of the page when you could've just read the summary and gained that knowledge. That template itself isn't even bad but it becomes a problem when you have 5 other templates doing the same thing right under it taking even more space. I came to this conclusion after seeing people on /soy/ complaining about templates whenever the wiki is mentioned. I think we can keep the weird/niche templates as long as we limit the number of templates at the top of a page, just one or two highly relevant boxes, 'za, gem/coal and gemerald/gemshort/coalshort/brimstone and no more.
Ultimately I haven't taken action to delete any templates after becoming a janny except for a few extremely low-quality ones, and even those I just mark for deletion or consult Sproke (as I do for all things I'm unsure of) instead of nuking myself. I just delete excessive templates from pages whenever I come by them. I also created {{Templatewrapper}} but that's more of a bandaid and just sweeps the real issue under the rug.