MacBook Pro 2017 stuck in strange half-bong sound loop, can't boot from anything

OK, a little embarrassing but I'll give the answer.

I switch between Windows and Mac frequently (work/home), and when I kept following the instructions for a NVRAM reset, I kept unwittingly pressing Control+Option+P+R instead of Command+Option+P+R. And so I tried resetting NVRAM several times having no idea I wasn't actually resetting it properly.

Once I realized this from a GIF animation on a website (a picture is worth a thousand words), I tried an NVRAM reset again and it fixed my problem.

Also kids - don't try installing Solus Linux on a MacBook Pro 2017. I tired installing it the first time and it corrupted the NVRAM like this. After fixing it with my instructions above, I tried again and it once again corrupted the NVRAM. Unlike many Linux distributions, It won't work.