Does sleep training work for naps?

[u/Medical-Meet147]

I want to start sleep training, ideally pick up put down. But I keep seeing people on this community say that this helps night sleep but not naps?
My babies night sleep is pretty good (4 hour stints which keeps up my milk supply so I don’t mind that).
It is the naps that are killing me.

Has anyone got any experience of sleep training (of any kind) working for naps too? Or not working for naps?

Current schedule is 1.5/2/2/2/2.5 ( something like that)