You make many valid points which I fully agree with. Trump had every right to pursue every legal option available to him - which he & allies did in the 65 legal suits they brought, 64 of which they lost - which should've dissuaded him from pursuing the matter further.
It didn't, even when his own appointees from the DOJ, WH Counsel, Cabinet members, State Judges, etc, had all told him there was no evidence of massive fraud which would have changed the outcome of the election. Rather than accepting that information, Trump double downed via pressuring State officials to do his bidding. Ethical Republicans refused to do so; corrupt ones willingly supported his lies.
After that strategy proved to be a failure, he sought even more corrupt ways of retaining power via embracing Giuliani, Sidney Powell, John Eastman & others unhinged illegal attempts to retain such, banking on SCOTUS ultimately saving his ass, given he'd appointed the latest 3. They didn't, which led to his next plot for January 6th; not only initiating the fake Elector scheme - which Pence refused to go along with - but also ensuring there'd be a large outraged crowd willing to go to the Capitol in his defense to disrupt official proceedings & try to prevent Biden from being declared the winner.
What truly disgusts me is the extent to which so many GOP politicians nationwide have gone along with Trump's lies - for self serving purposes - knowing full well the truth but refusing to ever expose such. They all need to be kicked out of office and/or prevented from every attaining such in the first place.