You are wise to be thinking ahead, but I actually think you/we should be fine. I think it is very unlikely that they will overturn the ACA, especially since the crux of the issue was the mandate, which has since been repealed. If they do overturn the ACA, I believe that any replacement will have to include a ban on considering pre-existing conditions, as this is incredibly popular across the political spectrum. If they allowed insurers to discriminate against those with pre-existing conditions, I truly think there would be a mass revolt and many groups would organize to get Congress to pass legislation to fix it. Finally, if all else fails and they do repeal the ACA and don't put anything in its place, they have to give insurers lead time to unwind their current plan offerings, which in my estimate would be at least 2-3 years (since plans for the next year are always designed/negotiated during the current year). So I think you will be safe, and in the event that you needed new insurance, you would have plenty of time to find a new job that offered it.
I am not looking forward to school starting if the decision is mostly or all remote. We're not quite in the position for one of us to stop working since we will be buying a house next year and will need to show stable income, but I am hoping I can request an altered work schedule that will let allow my husband and me to juggle the remote learning and getting our own work done, albeit in a more sporadic fashion. It's just a no-win scenario for working parents with kids.