Of course Raul, for one to try to compare a Cartridge that might be pushing 40 years old, such as a Shure V-15, regardless of how good the Cartidge was way back when, and how new the Stylus is on it currently, it would not be a worthy evaluation comparing such a Cartridge, with a new Cartridge of today.
Same would hold true, with a Dyanvector XV-1, ZYX UNIverse, Lyra Titan, 20-30 years down the road.
So, with that being said, users, such as yourself, Redtop, and countless others may in all actuality be giving truthful, accurate accounts, that would make a person like Redtop say, that "a crap Cartridge like the Shure V-15 was one valid reason analog took a mighty plunge with the advent of CD many years ago.
Of course, this is not true, and as an example, should I "hypothetically" decide to buy a used Dynavector XV-1 from a seller, a Cartridge that has recieved many accolades, just like the Shure V-15 III did many years ago, and get a poor, or damaged sample, it would then not be fair, or accurate to judge such a Cartridge, saying that the XV-1 was not as good as a "hypothetical" brand new $249 AT-150MLX, and that the XV-1 displayed "rolled off lows, and highs" such as Redtop once stated about the Shure V-15 III.
Opinions are of course like you know what, we all have them. And of course, under such circumstances, it then becomes hard to accurate judge-assess any given Cartridge.
And as you wisely point out as well, the different synergy from one system to another will have to be taken into account. Certainly, not one of us have the exact same system, with the exact same sound qualities to produce what would be a rock solid basis. And as wll, do we all possess the exact same ears, or sonic "likes". Mark