Cover letters — is anyone actually reading them, or am I burning my evenings for nothing?

I spend 30-40 minutes tailoring a cover letter and then half the applications don't even have a field for one. The ones that do feel like a checkbox.

Part of me thinks a strong project plus a referral does 10x more than any letter I could write. But then I get scared that skipping it costs me the one recruiter who actually reads them. What's your honest read — worth the time, or theater?