Even here in South Florida, the recommended pool temperature for comfortable swimming is 84-85F. Of course this time of year it’s running 89-90F with ambient air temp and sun! We use a passive solar (water pumped from pool to black roof panels and back) to have 80+ temps during our winter.
We would NEVER let guests control pool temperature.
My partner & I prefer indoor temps of 78-80F year around. That’s where we set the listing’s independent AC. However we do allow the guests to adjust to suit themselves. We do not, however, have long term “tenants” – we have guests who stay for only a few days at a time.
BTW AC’s “ice up” because the drain lines get clogged with slimy dripping “water” and do not drain adequately, regardless of temp. I use a small “shopvac” to suck out the drip lines at least monthly all year around.
Perhaps if your AC and pool heater are “struggling” so much, you need to upgrade them to more powerful units (you can take those costs as a tax deduction).