short answer to the op,
NO the 45ACP is not being phased out nor do I see any indication of it even slowing.
kimber, ruger, remington, springfield, smith and wesson, armscor(rock island armory/citadel) and wilson tactical all make a 1911 in 45ACP. if I am not mistaken less than half of those models have been around for more than 10 years.
in the polymer world, glock, ruger, springfield, FN Herstal, beretta, and S&W all make 45ACP models. it is still the most heavily manufactured cartridge in the world. 9mm has always nipped on it's heals and over the last decade of recession it has become even more popular as a cheaper alternative but it will not replace 45ACP any time soon.
an analogy, 8mm mauser, 7mm mauser, 303 british, 30-40 krag, 7.62x54R and 30 carbine all have been out of mainstream production for several decades yet companies still release limited runs of guns in those calibers and ammo can still be found at every corner gun store just about. 45 ACP was in service with the us military for 75 years and has been flooding the civilian market for the last 50 at least. I would seriously doubt that any time in the next 50 years if anyone stopped making ammo for it.
all guns lost in a tragic smelting accident.
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