I'd like to counter the bolded portion of your quote.
In spirit and in practice, I do agree with you. By far, most of my semiauto pistols are steel on steel and I own few aluminum alloy frame handguns.
Most of my handguns are for pure shooting enjoyment, I reserve only a select few for carry.
Steel on Aluminum guns are not of interest to me. Alu wears different and lifespan will be limited. Love carbon steel on carbon steel. Got a 226 Legion and that's the only exception. Not shooting it either. Recoil on Alu frame guns is also never as good as on a steel/steel pistol.
Intellectual honesty matters here. While the argument is true, you're talking about
tens of thousands of rounds typically, so you're talking about ammo costs (even if you handload) that greatly exceed the cost of the pistol.
Making the argument that an alloy frame won't hold up is much like the argument that only lead bullets are good for a barrel and that jacketed bullets are going to wear out a barrel much, much faster.
This argument is also technically true, but in actual practice, it's a questionable argument.
Another questionable argument is that a handgun that you
never, ever shoot with live ammo is certainly going to live a longer functional life than a handgun that you actually send 400 rounds through each year. True, for sure, but a very questionable argument.
Alloy framed handguns (especially S&W 1-2-3rd Gen handguns) have shown over more than half a century that they can handle a heavy volume of shooting and the volume of shooting required to attack the weaker alloy frame amounts to ammo that far exceeds the cost of the gun.
Similarly, traffic accidents claim countless lives all across the planet, this is not up for debate, this is true. If all motorized vehicles were governed to limit speed to 25 mph and never exceed, we could wipe out such a massive portion of traffic fatalities that it would be stunning.
We aren't going to do that. And an alloy framed semiautomatic is a phenomenal choice for a duty/carry gun for anyone who is going to wear that on their belt for 12-16 hours a day. Regardless of the "shortened" lifespan.