was expecting to find something like '0101010101010101010101010101010101010101010101010101010101010101'
This public key is also valid: 0401010101010101010101010101010101010101010101010101010101010101014D1FD6A5F1A2C
BD8536CF702611B753557B0841CA6B327F33C531903CA1A9428. And by hashing it, you will get another valid key, which is 02bab95d0a0de48828c93401baaf87e8fcd777c08bd972051abbe61ab4a49530cb.
However, it is recommended to use N-of-N multisig instead. So, if you have any TapScript, and for example five people put their coins in, then 5-of-5 multisig is better than some unspendable key, because then, there is a small chance, that all of them will be online, and all of them will be honest, so they will join their signatures, to spend those coins in a cheaper way (because spending by key is usually cheaper). And if any of those parties will be offline, then the outcome will be the same, as in case of some unspendable key. However: if the TapScript will turn out to be unspendable for any reason (for example mistake in endianness in the code), then it may be possible to spend it by key, and it may be useful, to experiment with TapScript, without burning coins.