Hard to say. Ultimately, I think Boris is a narcissist who wants to be worshipped. If he still thinks there's a chance to get his statue in Parliament Square, he'll stick around.
I think the perfect illustration of the kind of leader Boris is came during the exam crisis, during which of course he was on holiday and left Williamson to take the flack. But then the non-issue of Rule Britannia arose, and spotting an opportunity for the kind of shallow jingoism that made him popular, he made certain he was front and centre.
That's the problem. Brexit was perfect for him - he could give people their patriotic fantasy, blame other people (Remoaners, the EU, liberal elites) when it went wrong and leave his successor to take the rap when the worst of it hit. But the pandemic has been crisis after crisis where the buck stops with him, and I think he hates that. Look at the way he sulks in Parliament when he gets called out.