The alternative is that they don't install any firmware, your installation is broken or crippled, on another computer you search desperately for the correct firmware, which when you find it (on some byzantine and bitrotted manufacturers' website) has some impenetrable process that only works on Windows to install, is often buggy and broken, and there's never been an official update. If you need to manually intervene you might as well reinstall the OS because you didn't take any notes on how you did it last time, the manufacturers website has disappeared, and you're downloading the updated driver that might fix the bug from all-the-drivers.disco or a Discord server run by H4r&dw3r3-wiz4r&d88 who was probably not born in 1988.

For me, there's a huge leap from installing drivers that you're necessarily going to install anyway (because you're installing on the box that has the hardware) to adding optional stuff in. As long as it doesn't install the drivers silently, but installs them loudly. I'd love to even see a EULA pop up that indemnifies Debian from problems stemming from the nonfree drivers, to provide the appropriate level of intimidation and aversion. I would also request exclamation points, possibly a bright red or yellow color, maybe a blink.

I wouldn't be entirely against exclamation points, bright red or yellow, and blinking, for enabling nonfree repos, but there isn't exactly a high bar to jump over currently. The bar seems exactly high enough to keep everybody from complaining for very long.

The alternative to not install required non-free firmware is not an option we need to go back to.