feature toggles: do you use them?

my experience with projects that do trunk based development, i.e. a single branch and time-based releases, is that not all features can be ready when the release bell "rings", and something is necessarily half-baked. So you end up enclosing some code into "if (FEATURE_READY) {...}" so that it's there, but it isn't executed until a few releases later.

This carries some problems, like the explosion of the quantity of toggles over time, dead code that nobody cleans up, etc.