Do you really reckon it would have ended there? Seems to me that's giving too much credit to Pence, as if he's somehow the saviour of Democracy. Had Pence behaved otherwise (i.e. as Trump wanted him to) all hell might have broken lose, and there would have been a huge crisis, but I don't see that everyone would just shrug their shoulders and accept "oh well, Trump's still President then, I guess".
There were a whole lot of other things Trump would have had to have done to have laid the groundwork for a successful coup, and he was far too incompetent and short-term in his thinking to have done any of those things (I mean, he, and the Republicans in general, tried multiple different methods simultaneously, from court-cases to fake electors, to storming the capital, and trying to have electoral boards throw out votes, and none of them were properly co-ordinated - they were just wildly throwing everything at the wall and hoping something stuck).
I agree Trump attempted a coup, I don't agree it was ever likely to be an effective one. But there is of course always the Beerhall Putsch to bear in mind, so it's probably important that there be consequences for what he did, however botched it was. Plus I'm sure there are people in the Republican ranks who learned a lot from the 'experiment'.