[nulbyte]

We replaced VHS with DVDs. It took 42 years before we gave up on VHS. DVDs have been around for 29 years but were mostly replaced with BDs before disappearing off the shelves in favor of streaming.

We replaced records with tapes, tapes with more tapes, and more tapes with CDs before they, too, disappeared from the shelves in favor of streaming. Except that some stalwarts have successfully resurrected vinyl.

We replaced AM with FM, and analog radio with digital radio, then streaming. We replaced broadcast analog TV with digital, then cable and satelite, then streaming. Mostly.

None of these changes were backwards compatible, and all of them were meant for the general public. They took a while. They were successful.

[seydor]

The quality jump from vhs to dvd was massive. In comparison v6 doesn't offer much above v4

[krater23]

Yes, I've never played a DVD or CD on my Bluray player. That just didn't works.

[mnau]

Anyone who bought DVD player immediately had the benefits of better quality. The same applies to all other examples.

The problem with IPv6 is that you don't get benefits. If the designed protocol needs an equivalent of big bang, it's doomed. ASCII->UTF8 didn't need big bang. x86 to Itanium needed big bang.