-- On a percentage basis, the incidence of serious illness or death was material, but not unheard of. The problem was the combination of (1) that strain of COVID was highly contagious, and (2) it was new, so there was no immunity of any sort built up in the population.
So while the percentage of serious illness or death might have been manageable, you had a massive top line number of people getting sick. So an otherwise manageable percentage of serious illness or death translates into a huge number of bad sick and dying people, overwhelming the healthcare system.
-- We still don't know for sure. But it's looking more and more like it originated in the lab. Early on, Fauci himself felt that the animal market wasn't the source but rather the first place where there was close contact amongst people who theretofore hadn't been exposed, with people who had. Which made it the first super-spreader event.
-- But when evidence (as distinct from proof, which we still don't have) started pointing to the lab as a possible source, the mainstream media started labelling anyone who called it out as a loony conspiracy theorist. Turns out they might or might not have been right. As arthurdawg states, I don't think we'll ever know for sure. But it was definitely not a baseless contention.
-- This was another instance of the scientists and mainstream media arrogantly telling the public to get in line and mind their betters. Which didn't go over so well and caused a bunch of people to solidify their opposition.....if only so they never had to admit they were wrong.