This is not true.
I've spent a lot of time recently collecting mob stats for project EQ (the most popular emu database), and I still have my old logs. Velious raid content has the same min and max hits today as they did 12 years ago. PoP mobs all have slightly reduced DIs for some reason (which means reduced max hits).
Torrin-Vindicator+Statue.txt 1227 [Thu Oct 18 20:49:12 2001] The Avatar of War hits YOU for 1154 points of damage.
eqlog_Torven_test.txt 121520 [Tue Jan 28 08:22:58 2014] The Avatar of War slashes YOU for 1154 points of damage.