So...what's the draw of Biden?

[better]

119. I suspect it's not asking for arguments that resulted in such negativity.

Seems much more likely that the way you phrased your OP conveyed contempt for arguments such as "he can win" as "a garbage argument" gave rise to it. Ultimately, some of your more thoughtful and measured responses to objective posts do tend to indicate that you are at least trying to keep an open mind, but your initial phrasing unnecessarily (and quite possibly unintentionally) invited negativity.

One cardinal rule of communication that I always try to follow (and sometimes succeed) is to avoid putting my audience on the defensive, because the productivity of communication invariably suffers the moment one party becomes defensive. Whether I should have to "coddle" anyone, be "PC" or whatever other derogatory connotation one might apply to this concept, the fact is that my objectives are hindered by failing to avoid putting my recipients on the defensive, so avoiding it is worthwhile.

Had you phrased your OP, for example, more along the lines of "I get the significance of picking a candidate who can beat Trump, but that's not enough for me, and I think several other contenders could as well. What other aspects draw you to Biden?" would have conveyed the same concern and elicited the same input, but avoided many negative reactions.

We're all a bit chafed by events of the last two years, so even our allies are subject to reacting a bit more harshly than is really called for, as we are after all only human.