Is your feature request related to a problem? Please describe.
OptiFine has added the new system for resource packs which supports components, so some new packs can use them instead (as OptiFine recommends them in the documentation, and the NBT category is no longer highlighted, there will be more and more component packs). But EMF and ETF don't support them.
So, instead of nbt.n.tag, people will start using components.n.tag (if they haven’t started already).

random_entities.properties still has NBT mentions, but it calls us in cit_single.properties https://github.com/sp614x/optifine/blob/master/OptiFineDoc/doc/random_entities.properties

In cit_single.properties, components are highlighted https://github.com/sp614x/optifine/blob/master/OptiFineDoc/doc/cit_single.properties

NBT is still here, but only as comments. It looks more like something archived

Also, in the community-created wiki, it has been removed. I can't remember exactly where I found it (maybe in some guide), but in my browser, it appears first when you search for "Optifine documentation". https://optifine.readthedocs.io/syntax.html#component-format

So yes, more and more resourcepacks will use this. But now ETF and EMF skip this attribute

Describe the solution you'd like
Add components support in properties for EMF and ETF

Does OptiFine do this
Yes
components.n.tag in .properties files

Additional context
models.1=2 name.1=iregex:(Reuben|Beuben) components.1.Age=(-10000)-0

Custom model with different UV for example

Forge Optifine (works, but model is broken somehow)

Fabric EMF ETF (dont work, just skiped attribute)

am I missing something, entities still primarily use nbt data, this only really applies to items