The islanders can't govern who visits, but if you are going by ferry, Calmac have been introducing rules to stop some visitors.
Scottish restrictions are published and you can check your proposed activities to see if they are legal. I was to visit my home on Skye next week, but my brother is there so now I can't as households can't mingle.
As a Sgiathanach I can tell you that the locals are divided about visitors. Those that rely on it for a living want it, but lots of others resent it. The island communities are many hours from hospitals and have an elderly population. In the current climate it's worth being extra careful if you go.