I suspect that there's more than a little by way of crossed wires here.
Some are talking about how to achieve the best sound for the band, some are talking about achieving the lowest weight and/or cost, and some are talking about other things entirely.
If I was in a professional functions band where we all earned (most of) our living from playing in that band, then the PA-based route would clearly give the best results for band sound, the cost could be offset for tax purposes against the band's gross income, and I would expect the entire band to buy into that solution.
But I'm not. I'm either an enthusiastic amateur or (at best) a semi-pro, earning what amounts to pin money for indulging in my hobby. I play in multiple bands, sometimes for years and sometimes for weeks. Whether or not I might like my entire band (whichever one we're talking about just now) to go through the PA, I have absolutely no choice but to own a bass rig.
If that makes me a "Dino" then I'm cool with that. In truth, though, I think that makes me quite sensible. Turn it on its head. How would you describe a drummer without his own kit, or a guitarist with no combo? I suspect that the word "idiot" would be one of the milder terms. A bass player who can only function in an environment where five grand's worth of PA is supplied is of limited use.
Now me, the "Dino", I can function in an environment where five grand's worth of PA is supplied, AND I can function in any other bloody environment too.
What's not to like?
And this isn't just about me, the bass player. What about the rest of the band? If I become a PA-based player, am I really going to have to find a PA-based guitarist, a PA-based keyboard player, and a PA-based drummer to play with? That rather limits the opportunities, don't you think?
Just because something is a really great idea in theory (and a PA-based band is a really great idea, I like it) doesn't mean it will always work in practice, still less that it will be a better solution than the one you already have.