Breton. With Welsh, Irish and Scots Gaelic, children have some impetus to learn it as a second language at least. But the problem for Breton is that for almost all speakers, French is the first language, and parents want their children to learn English as a second language. Breton comes in a lowly third at best. This is disastrous, as we're losing whole communities of speakers with each generation. It also means many if not most speakers come to it later in life and never achieve native fluency. And the French government not only doesn't support the language, it actively discourages its use.
Here in the UK, I've stayed at 4* hotels that charged £20 a day ($40) for internet...and that's not even in room. I've also stayed at magnificent hotels that offer free in-room internet, with free wi-fi in the lobby. (Malmaison, I'm looking gratefully at you!).