Nancy Pelosi had to know when she decided to impeach Trump that the day would eventually come when she’d have to sit behind Trump at the State of the Union after his acquittal or close to acquittal while he made the case for himself in his inimitable style. (The only way to avoid this would have been not to invite him.) Still, she couldn’t hide her frustration and ripped up the speech at the end, in what the address will probably be most remembered for. It’s not as though Trump is one for grace notes — he didn’t shake Pelosi’s hand at the beginning, almost certainly deliberately. But Pelosi has tried to keep her caucus from juvenile displays and engaged in a highly memorable one herself.
Overall, the disparity between the outrage of the Democrats and how the general public received the speech was probably vast. Trump exaggerated and pushed the envelope for SOTU showmanship, but besides on the key cultural issues of abortion, immigration, and guns, it was a relatively centrist speech. He touted the good data on the economy, highlighted a lot of moving stories from the balcony, and talked up unobjectionable initiatives like planting trees and getting to Mars.
Anyone not already committed against him had to wonder why Democrats were so angry.