from the teams perspective you may be right but the spectators are the real losers
look at the 2003 season you had totally sureal scenes of VW Golf passing Ferraris and Porsches or some ancien cars like a Ferrari F40 on the grid mixing up with the newer cars
GT3 category is a blessing and curse at same time (just like TCR) it ensures relative decent sized grids and relative chances but it completely kills off variaty and makes the whole sport dependent on the big manufacturers, it also kils off the "identity" of a championship since every one of them uses the same cars (not just same rules)