Scheduled sex is itself fine, however most men (at least those worth considering as a long term partner in the first place) derive much, if not most-all, of their enjoyment of sex of the human connection, and feeling the desire and arousal of their partner.

Sex with someone who isn’t enjoying it, and just passively accepting does not sound appealing at all to me, and I’d be weary around men who are open accepting such an arrangement, because imo it strays into areas of ambiguous consent.

At that point, it’s probably similarly enjoyable, and much healthier, if your partner takes of their urges by masturbing. You could potentially even support a future partner in that, by e.g. gifting him sex toys like fleshlights. It shows that you genuinely care about his pleasure, even if you’re not into actively participating in sex. This is for example a relationship I (as a cis man) could exist in perfectly happily.

And whilst it’s obviously not everyone, and it can be emotionally challenging, I would also consider the potential for an open relationship, where your partners urges could be satisfied without your participation.