In general I believe that federal officials must be immune from prosecution for exercising their official duties. Virtually anything a president or Congress does will be vigorously opposed by someone. Sometimes official acts result in damage to individuals or institutions. There are so many moving parts to anything that the government does that the chances that there will be no problems or negative consequences approaches zero. Two examples of presidential decisions that went wrong are Trump's handling of Covid and Biden handling of the withdrawal from Afghanistan. Both resulted in chaos and death, and it could be argued that there were ways to address both that would have yielded better outcomes. But hindsight is usually 20/20 and it could also be argued that both of these decisions were made in good faith and that neither should suffer criminal penalties for not being fortune tellers. We elect people because we believe that they are best suited to represent us and to competently manage a crisis. Sometimes there's no 100% right answer where everybody wins.
The alternate excuse, that attempting to overturn the election, including not just Trump's speech on January 6th, but all shenaniganesque machinations that led up to it, were part of official duties is nothing short of absurd. I've commented multiple times about the many acts that Trump took to undermine faith in the system as well as illegal end runs around that system, so I won't recap them here. But his actions certainly don't fall within faithfully executing the office of the president or preserving, protecting and defending the Constitution.
Trump and his people like to say that he's being targeted to prevent him from being re-elected this year. In my opinion it's more a case of the chickens coming home to roost. He has spent his whole life avoiding accountability for his actions because he had enough resources to stall the legal system and wait out his opponents. He did whatever it took to secure his own paycheck. Getting elected in 2016 just made it worse. He laughed at campaign laws and welcomed assistance from Russian agents. He monetized the presidency. His final acts were an attempt to retain power. He and his cult allege that all of the indictments are the result of a hatred that Democrats have for him - frankly I don't care what the motivation is for these investigations, in each case a grand jury of ordinary citizens thought that there was sufficient evidence to indict.
Hope there's plenty of roosts for those chickens.