This seems to be the case. I saw your reply on Bitcoin StackExchange as well. In bitcoinj I just made it so the client only connects to nodes with at least protocol version 70016. Seems to work well.

‐‐‐‐‐‐‐ Original Message ‐‐‐‐‐‐‐

On Wednesday, November 17, 2021 7:00 PM, Pieter Wuille via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:

On Wednesday, November 17th, 2021 at 1:07 PM, Andrew Chow via bitcoin-dev <bitcoin-dev@lists.linuxfoundation.org> wrote:
Prior to 0.19.0, creating outputs with an unknown witness version was considered non-standard. This was a violation of BIP 173 and was fixed for 0.19.0+ in PR #15846.

That's correct, but I think OP's problem is with getting P2TR _spends_ to relay. Those will be rejected by all post-segwit pre-taproot Bitcoin Core releases, as far as I know.

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Pieter