In base-recipe-changes.lua, you're checking if either "Glass" of Crushing Industry (CI) is enabled or AAI industry exists to change holmium and electrolyte.

In CI these are changed regardless of glass being enabled, it only checks for space age. (Line 39 here: https://github.com/SafTheLamb/fm-crushing-industry/blob/main/base-data-updates.lua) So you can always have those changes being done if space age is present.

Noticed because I'm trying to do compatibility with this mod and was looking through the code :)

Also shouldn't the below line be a "replace" for the holmium powder change for holmium solution?
frep.modify_ingredient("holmium-plate", "holmium-solution", {type="item", name="ei-enriched-holmium", amount=1})

To make compat a little easier I viewed (sand/)glass/quartz as one pack. Sand is a bit of an outlier because it's also a by-product from crushing. I think my perspective back then was "if user disabled glass, quartz has no use".
Now I see that there is potential use for quartz, thanks for pointing this out. I will attempt to put it in line with CI and maybe add separate Mod-Settings for quartz.

Also thanks for doing compat, much appreciated! A little heads-up: the names of the Mod-Settings will change with version 0.2. From what I've seen, there is no easy way (if at all) to migrate these. So I want to make sure the names are final this time. (Hence this may take some more time.)

I think I used modify because it changes from fluid-type to item-type, but that's more of a guess …
It seems to work so far but I will check.