First off, Trump's little "two crumbs" happen every other day and usually involve something a bit more serious than Obama wearing a tan suit. For instance, who could forget when Trump's expert geopolitical strategy, outclassing even the Pentagon, had him saying he'd be leaving Syria. Now the thing about this is that he didn't even leave Syria, and if he did he would be totally ditching the SDF and practically giving Syria over to Russia and Iran. For a more recent and highly regarded example, who could forget Trump cancelling a scheduled trip to Denmark after they refused to sell him Greenland or when Trump sent a message congratulating Poland during the anniversary of the German invasion of Poland, which any tasteful president would know is an event to be somber at, not one to say "We also have many Polish people in our country; it could be 8 million. We love our Polish friends" (which he actually said, no mention of World War II or a fifth of Poland's population dying or anything, just Poles in America).
Second off, Biden's getting hounded on by leftists. He's among among the most right-wing presidential candidates in the Democratic running. I don't know how you define "leftist", but for me far-left means any of the various forms of Communism, left means socialism or some forms of social democracy, and center-left means some forms of social democracy and neoliberalism. Biden falls around the neoliberal category, I wouldn't classify him as a social democrat by any means. He's simply the most popular democratic candidate because of how moderate he is and his connections to Obama.
Your gripes about Biden are valid, and he was getting roasted hard in more recent debates for that. I'm not exactly a fan of him either (I'm more of a Buttigieg kinda guy). But don't pretend like Trump's a little angel either, his gaffes far outclass Biden's in my opinion.