script – What sort of pockets or protocol would signal a Taproot keypath spend with SIGHASH_NONE?

Searching early Taproot transactions, I got here throughout this one (block 709,911, ~280 blocks after Taproot activation):

https://mempool.house/tx/ef72502f5d2509f519be33304e385bdf9d1bed5e4cd19f7a254700299db2ba91

What caught my eye:

1. It is a P2TR keypath spend, single enter, single output, dust-level
   quantity (1943 → 1803 sats)
2. The witness signature is 65 bytes ending in 0x02 — i.e.,
   SIGHASH_NONE (not SIGHASH_NONE|ANYONECANPAY which is 0x82)
3. nSequence is 0x9f (= 159), which below BIP68 would suggest a relative
   timelock of 159 blocks

Plain SIGHASH_NONE (with out ANYONECANPAY) on a 1-input-1-output transaction appears unusual to me — the signer is actually saying “I authorize spending this UTXO no matter the place the output goes,” however there’s just one output. Anybody seeing this in mempool may in precept change the output and rebroadcast.

Questions:

1. Is there a identified pockets or protocol that indicators P2TR keypath with plain SIGHASH_NONE (0x02)? I would count on 0x82 (NONE|ANYONECANPAY) for any sort of cooperative signing stream, not 0x02 alone.
2. Is the mix with the weird nSequence=0x9f indicative of a selected check framework or early growth software from late 2021?

Curious whether or not this can be a identified sample or only a one-off oddity.