How so? I think you're just confusing "liking the franchise in general" to "liking the games". There's tons of Touhou fans out there who has probably never played the games because they don't like bullet hells, but the games are very solid bullet hell games for those into the genre.
I would tend to agree that Touhou games are overrated by their fans
, but I would also tend to agree that they're pretty fine games, on the whole. The Final Fantasy comparison isn't a bad one at all, particularly if you look at FFVII; it's a very good JRPG, but isn't the Best Game In The History Of All Games that some of its fans will claim.
It seems to me that they offer a distinctly different kind of experience to some other bullet-hell games, though. Touhou games are (at least partly, if not predominantly) about spectacle, but in the same way as Saving Private Ryan
and Jurassic Park
(or recent Final Fantasy games!)are about spectacle... it doesn't make either of those bad movies, and it doesn't make the Touhou games bad bullet-hell shooters.
I'd agree that Perfect Cherry Blossom is a good introduction to the series (I'd avoid Imperishable Night because of that weird time-related mechanic that makes no sense to the beginner) and that Shoot the Bullet is a great game that's quite useful for skill-building as well as just being-fun.
(And man, that rack of animated smileys up there doesn't half make a remote desktop connection grind to a halt...)