Not all McDonalds use the Taylor machines. Some use machines from other manufacturers such as Carpigiani [2]
Taylor’s the largest manufacturer of commercial ice cream making equipment in the US. Franchisees also have the option of using Carpigiani machines, but they’re Italian so parts and service are not as easy to come by. And all ice cream machines are known for being easy to break, especially if used by poorly trained teenagers.
This also makes no sense, if McDonald’s wanted to make more off the franchisees from ice cream, surely they’d rather do it by having the machines work (so they can sell product). They sell the mix that goes in the machine to the franchisees. It would be idiotic to try to gouge them by making the machine crappy rather than just charging them more for the mix and using a good machine. Then they wouldn’t need to employ these imaginary service techs and the franchisees would be happier with the situation.
Occam's Razor suggests that the most likely explanation is that the McDonald's Corporation is deliberately setting their franchisees up to fail by continuing to sign contracts with Taylor. Which I agree makes no sense.
Occam’s razor might suggest that their competitors use a different machine entirely (I really don’t know but Wikipedia’s page on Taylor only mentions McDonald’s).
McDonald’s corporate making a bad decision about a machine seems a whole lot simpler than some convoluted conspiracy theory, doesn’t it?
That excuse wears thin after 10+ years.
I’m sure they’ve done the math somewhere, and possibly determined this is more of a meme than an IRL business liability