It is worth remembering that, as Boris would have it, we "got Brexit done" in January 2020, where we lost most of the things Remainers cared about, but because we are subject to all the rules we have gained few of the things Leavers cared about. If we delay, we are definitely in a BRINO situation where both sides are getting very much less than they wanted.

No one knows how long the impact of coronavirus might last, but several years to get back to where we were at the start of 2020 is by no means unlikely.