Yeah, I was having a long discussion about this with a friend, and this is precisely where the misconception lies.
The problem with the 32->64 transition (or x86->ARM) doesn't lie with active businesses failing to "get with the program" and update their software - it lies with abandonware. With software that's been put out either by defunct companies or sometimes literally deceased programmers.
In some niches, this sort of stuff is really, really common - generally this is the case if there's a really stable API for building things, like VST plugins, and if the niche in question has a lot of failed businesses. A lot of times in the pro audio space, a musician will spend a large part of their career "collecting" a ton of little one-off sound libraries and fx plugins, because these are the only way they can get the computer to produce that exact kind of sound they're looking for. This collection slowly builds up over the course of, say, a decade - just like a graphic designer would collect fonts.
The difference is that unlike fonts, which last had their "greet the reaper" moment back when bitmap fonts got scrapped in the mid-90s (despite OpenType becoming a thing, TrueType fonts from the 90s still work fine, some 30 years later), any audio plugins that aren't compatible with the cpu architecture die out. And that's just really brutal to a working musician.
You can't get an update to most of those because there's a ton of attrition in that industry; lots of small-time plugin makers realize pretty fast that it's a very difficult place to make any kind of ROI, so they quit after a few years.
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Games are in a really similar place - they're a business slaughterhouse where most companies that attempt to make something discover they're not going to cover the initial investment, so after the game's produced it typically gets a couple of years of barebones support, and then gets abandoned - or the company just croaks. Any kind of rewrite is completely out of the question. The tragedy is that most of these games are pretty good and fun, they're just not economically viable.
I love apple moving the tech forward, but we desperately need a better emulation solution, and/or we've got to get the industry off of coding for bare metal.