I think a fair response is that McIntosh makes decent stuff, some of which is quite good sounding. I do not know what current production build quality is like. It's important to point out that the company has gone through a number of ownership changes over the years, but manufacturing has always remained in Binghamton, which, unless the ownership changes featured large work-force reductions, suggests that experienced techs (and new techs overseen by experienced techs) have always been used to manufacture the gear, a very important thing.
It's also fair to point out that there are a number of newer manufacturers that make better gear, and in some cases, much better gear, than McIntosh (in order to avoid controversy, I won't name any brands). But it's also true that such gear tends to be more expensive. Because the quality of the output transformers and size of the power supplies are critical factors in the sound of a tube amp (the other most important element being the choice of tubes), and because quality output transformers and power supplies add both expense and weight to the amp, the quality of a tube amp can generally be determined from its price and weight, i.e., the heavier and more costly a tube amp is, the better it sounds, generally speaking.
Like B&W speakers, McIntosh is one of the few high-end audio brands that non-audiophiles have heard of, and as a consequence, new audiophiles who lack knowledge of other manufacturers often buy McIntosh (and B&W). This increases resale value and is another good reason to buy McIntosh. Many experienced audiophiles have had the experience of buying really expensive high-end gear that is little known in the broader audiophile market and therefore quite difficult to resell.
It's also fair to point out that there are a number of newer manufacturers that make better gear, and in some cases, much better gear, than McIntosh (in order to avoid controversy, I won't name any brands). But it's also true that such gear tends to be more expensive. Because the quality of the output transformers and size of the power supplies are critical factors in the sound of a tube amp (the other most important element being the choice of tubes), and because quality output transformers and power supplies add both expense and weight to the amp, the quality of a tube amp can generally be determined from its price and weight, i.e., the heavier and more costly a tube amp is, the better it sounds, generally speaking.
Like B&W speakers, McIntosh is one of the few high-end audio brands that non-audiophiles have heard of, and as a consequence, new audiophiles who lack knowledge of other manufacturers often buy McIntosh (and B&W). This increases resale value and is another good reason to buy McIntosh. Many experienced audiophiles have had the experience of buying really expensive high-end gear that is little known in the broader audiophile market and therefore quite difficult to resell.