You must understand that most anons admittedly, myself included
PROBABLY have this self-insertion with Finn's character. And, over the years (at least in the first couple of seasons) despite his shortcomings and mistakes, we'd still find ourselves rooting for him, because there were still episodes that belittled him all through out them (examples: Blood under the skin; Ocean of Fear) So again, please understand that these so-called "incels" you are referring to are not all incels. >Inb4 not all X/Y
Well, in this case, it's just empathetic passion that some people just long for to keep in these trying times. Nostalgia is a huge factor in this.
TL;DR - Fuck yourself with a rusty spike, you fag enabler.