Free has ipv6 enabled on 100% of their customers, and while sometimes their software has a few issues, it's working perfectly fine. People just get pissy because Free refuses to pay for peering with Google for e.g. Youtube, and it feels slower, even more on v6.
The only ISP not putting out v6 widely is SFR, and thankfully they've gone bankrupt and we will be rid of this scourge.
I am on Free (after a few years with Orange because Free could not bother to provide fiber here) but I am considering switching to Bouygues because I pay too much for the connection.
The connection is solid, though - thus my lack of enthusiasm.
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