To be fair they basically released two dynasty warriors games a year for about a decade. These giant, review proof games would end up on your desk every six months, and that's before they started the other franchise collaboration games.
DW games are a reviewers nightmare.
tbf those games were generally expansions. Xtreme Legends (which by the way they can't name it that anymore due to a Capcom lawsuit) and Empires are very much expacs. (Empires is kind of its own thing though). I understand it sucks as a reviewer, but like, that's part of your job is too play these games. I would feel it would be better to mindlessly run through Dynasty Warriors for a bit rather then play through a shit ton of licensed garbage.
The PS2 days were weird for game reviewers anyway, it was right at the start where I think western game reviewers got sick of Japanese games (IGN's infamous God Hand review is the most famous example) which came to the western dominated last gen, which, Ive seen is that reviewers kind of got sick of western game design and are starting to appreciate Japanese games a lot more. Monster Hunter is another game that was despised by game reviewers.