idk about coreclr but the current gc isnt great either in my experience but that might be the unity games i play being real bad about that sorta thing lmao
I think unity is just a bit crippled due to the company constantly ripping out and shoving in things because they're desperate to show investors they're worth the effort
I think basically every feature in unity atm is like.... the functional stuff is (DEPRECATED) meanwhile the replacement lacks like 50% of the featureset of the old version