If the Tories were to publicly depose Boris and then call a snap election, I reckon they’d get a big enough bounce to get another majority.
The Tories will definitely replace Johnson now as he has become an election liability who can’t reasonably recover.
I can’t see any obvious advantage in them calling a snap general election though. They currently have a huge majority which whatever the outcome of the next general election they are very unlikely replicate.
Huge majorities are highly desirable as they make rebellions almost certainly ineffective and make legalisation incredibly easy to pass.
Furthermore until Johnson’s first **** up over Paterson the Tories had a consistent lead over Labour, the only reason the Tories have trailed Labour by a few points since last November is because Johnson has had one **** up after the other, there is no reason to assume that with him gone the Tories will not re-establish a lead. Unless they choose another blunder prone idiot in which case they will probably lose the snap election anyway.
As long as Starmer stays Labour leader until the next general election the Tories can reasonably assume to remain in government for at least the next 6 years. If they call a snap election and they win it Starmer will definitely resign and the most they can be sure of is to be in government for the next 4 years.