it's not that it's popular is the problem - again, so we're clear, there's nothing wrong with liking popular things
the divide here is that there's a difference between liking a thing and making the fact that you like a thing part of your identity, and accepting that an unavoidable reaction to the latter is people interpreting your thoughts and opinions and actions through a lens shaped particularly by their impression of your identity
for example, if you choose to identify as a furry (and there's nothing wrong with that!), you have to come to terms with the fact that a lot of people are going to assume you're a socially stunted person who wants to have sex with animals (because that generally seems to be the case!)
more to the point, there's a huge movement of people called bronies, as I'm sure you all know, who've become somewhat infamous for generally being incredibly ignorant in most social capacities, and trying desperately to make their love of the cartoon the central tenet of their identity because of what they believe that communicates to other people in a social capacity
i.e what they think being a person who likes ponies says about them is more important to them than actually liking ponies
why this is relevant to Strong Bad's opinion about a thing in Smash is that it immediately colors him, to me, as a person who's more concerned with coming across as a person who believes a certain thing than he is with actually putting what he believes on the line
i.e that he thinks "more options means more depth" is more important to him than whether or not that's actually a meaningful or valid way of thinking about it, and since determining whether or not that's true would seemingly not be very high on his list of reasons for engaging in the discussion about it in the first place, his opinions about it are as such irrelevant, as they're more a tool through which he attempts to solidify his identity than they are a means for me or him or anyone else to learn or grow or change in any meaningful capacity via social interaction