Hey! In general, feature flags are used as a way to roll out changes, and to be able to roll them back in case customers encounter issues. Bitwarden has no control over these on self-hosted (and does not generally support them on self-hosted), so self-hosted users get these features whenever the flags are removed and the features are enabled by default.
If as a self-hosted customer, you want to get these features now, you are free to configure your instance to enable these. You can enable ssh-keys and ssh-agent right now using feature-flags on a self-hosted instance. But beware that these are feature-flagged for a reason.