Forcing users to use a specific browser to use certain features on site may be better than the "since all browsers don't support it, I am not going to implement support for it" stance.
Nobody's going to force which browser I use. Imagine being blind, having paid more money than you have for a screen reader, written way back in the day and only even works at all with IE6. Yeah, let's see you force them to some other browser that doesn't work with their reader so that other people can get sparklies bs on your web page.
Or, wait, here's a revolutionary idea... let's put the sparkly flashy junk on our pages and whichever browsers are evolved enough to show it, show it... and all the other browsers simply don't, yet can otherwise render the page!
Wow, brilliant. Wish I'd thought of it.
I know some people see the innerwebs as something like cable tv... you don't need it and you only get it if you're rich (or on welfare, I never understood why it works that way). But the internet is slowly becoming a necessity... around here, our banks are closing their brick and mortar buildings and telling their customers to do everything online. Seriously, I need access to my bank. "Best Viewed in Proprietary Browser Who Only Runs On Proprietary OS" is so not happening. Let's not go back to the Bad Old Days of segregation and separate fountains.
That this guy works at Facebook makes total sense though: my Konqueror (DESKTOP) browser always gets sent to some (doesn't work) WAP page, as if it were a mobile.