You know, some people buy a metal truck box and bolt it to their cargo carrier, then lock the generator in it. Protects it from the weather, and if thieves can't see the genny, they won't know it's there to steal it.
A box like this is not cheap, but you can think of it as a lifetime investment. Or you might be able to find a used one on Craigslist.
Some people even modify boxes like this to run the genny inside it. You can find YouTube videos showing this if you search.
Here's one example:
https://www.northerntool.com/shop/tools/product_200620936_200620936