[unwiredben]

I don't think HEVC will go away; there's already a lot of fixed-function embedded hardware out there with HEVC decoders that will never get AV1 support. All the streaming players have to support those for the foreseeable future.

[shmerl]

Hardware gets obsolete. Fees for HEVC do not, so new hardware won't be using it. For the legacy support, video services will use H.264 like Youtube does now. They just won't offer higher resolution in such cases, which is fine.