I suspect nihilism is often opposed on grounds less superficial than this, but on a surface level you’re likely encountering people who think of it as “cheap philosophy” simply because the implications of it being true don’t sit well with them on some emotional level or another. You see this sort of sentiment even in the top comment here where /u/Sifloki7 writes “This is the way I look at it: Nihilism simply isn't a practically effective way to live”.

The basic typical position seems to be that even if nihilism is accurate, we nevertheless ought to go on living as if it isn’t.

This isn’t really an argument against the validity of nihilism as much as an argument against not wanting to live as if it’s valid. I don’t think this is a great antidote to arguing against nihilism, because I don’t see much reason to believe that intellectually arriving to nihilism will result in “practically” living nihilistically. I won’t be writing enough here to properly justify what may come across as bland scientism, but the mechanics of the human body (barring depression, etc.) will simply manifest on continuing on as if there’s meaning even if you intellectually surmise meaning isn’t there.

I don’t believe that “actual nihilism” in terms of academic philosophy is going to cause someone to never get out of bed, or do any work, or socialize, etc.