Unfortunately the only way to opt out is to uninstall the current version of the extension and install the last good version, which is on the Bitwarden github here:
Something I have noticed a lot of in the past several days is that soooooo many users (including myself) keep asking “why? WHY? WHYYYYY?” and that above everything else is the biggest indicator that this UI redesign is a failure.
In any interface, if everyone is asking that over and over again, you are making changes that are not improvements. Should have paid attention to that in the beta, because I saw the same feedback from that.