Earlier quoted context omitted.
Natural gas cannot be replaced by nuclear energy (or any other source of electricity) for many applications, at least not in the short term. For example here in Germany, many homes use gas boilers (heaters) for heating space and water. You would need to rebuild a lot of infrastructure to use electricity (which Germany plans to do, but obviously this will take years if not decades).
Electric heaters are cheap (it's just a glorified resistance). It's easy to switch home heating from gas to electric (with portable devices). Maybe not for every room but enough to survive a winter or two. Water heating is more complicated.
Hopefully the government is already incentivizing switching to heat pumps, but that's not a quick solution.