They removed USB-A about a year before they should have, but now the industry has moved on. We can talk about it as a mistake in the past, but it would be wack to put USB-A back onto these devices.
How can we say "the industry has moved on" when the second piece of media on the linked announcement page has someone doing music production with a visible USB-C -> USB-A dongle connecting some rack-eared music gear. There's even a second dongle on their left that I don't recognize. I long for the C-only future, but we're not there yet. Apple's decision to go C-only always seemed to be an aesthetic one to me.
That was true last year.
This year, it's been smooth sailing at every conference so far.
I literally dealt with a broken hub last week. I have no idea what you’re talking about.
That's been my experience: at every conference I've talked at this year (three so far: ESUG, Macoun and SPLASH, heise MacDev still coming up in December), I plug in my USB-C equipped MacBook Pro and It Just Works™.
Only one of those was an Apple-specific conference.
Sorry your experience is still different. Mine was, too, a year ago.
There needs to be a transition period where everyone has USB-C and USB-A so that the peripherals can naturally move to the better technology.
Right now I've never seed a good USB-C to USB-A converter. I work at a lot of conferences, and any time a speaker comes with a new MacBook and a USB adaptor, it's a disaster. They all suck.