The Marvell chipsets are awful, this is true. However, I think the only 802.11ac chipset that currently works with Linux is Intel, since Atheros hasn't been Linux-friendly ever since they were bought out by Qualcomm.
As far as I'm aware, there are no WiFi dongles that support 802.11AC. I think your only option is internal. So if you want to connect to a 802.11ac network on a Linux desktop your only option is connecting through a wired connection with a bridged 802.11ac router or something.
I don't personally mind, but I do think it's bad for the adoption of Linux. Most people I know only have Laptops, and if people can't get their WiFi working they aren't going to use Linux.
As far as I'm aware, there are no WiFi dongles that support 802.11AC. I think your only option is internal. So if you want to connect to a 802.11ac network on a Linux desktop your only option is connecting through a wired connection with a bridged 802.11ac router or something.
I don't personally mind, but I do think it's bad for the adoption of Linux. Most people I know only have Laptops, and if people can't get their WiFi working they aren't going to use Linux.