Maybe, but that's not the point.Most of the bands there are black metal which is pretty different from death metal. But, I know while TGP is generally willing to have deep, philosophical discussions about the various permutations of blooze they think the exact same sort of attitude in metal is childish or stupid.
Well, historically, black metal was in large part a reaction to/against death metal so it's almost like saying thrash and glam metal are basically the same thing because they can both be termed metal and have some common musical influences.Maybe, but that's not the point.
Someone posted a link to a pretty funny site with a catchy name ("Ikea or Death") that tests people's ability to distinguish between an Ikea product name and a black/death/speed/extreme/etc metal band.
The "or Death" trope (and its variants) is common in English--e.g. "give me liberty or give me death", the "funny or die" site, "your money or your life", etc.
It is true that the metal bands therein are not all death metal stricto sensu. Some are black metal, some are death metal, some are experimental, etc. But the site's owner is allowed some poetic license and/or inaccuracies of this sort because the name they chose is clever, catchy, and close enough--if one grants that "death metal" is a rather large subgenre of metal, like glam, heavy, thrash and speed, it is the closest of those large subgenres to the various genres on the site (viz. black metal and related).
In addition, the cost (as measured in units of catchiness) of being accurate would have been rather high when one considers the fact they likely had to pick bands with names that sound like the Swedish or pseudo-Swedish names Ikea uses, in order to make the quiz more difficult and amusing. Disproportionately, extreme metal bands from Scandinavia and thereabouts are more of the black or symphonic variety, rather than strictly death metal; had the site's owner chosen accuracy, their site's name would have to have been "Ikea or Black" or "Ikea or Symphonic Black", which is--surely you will grant this--not as catchy and amusing as "Ikea or Death". Hence the liberty with the inside-baseball minutiae of extreme metal subgenres.