As long as the certain RV park allows year round stays because RV parks are usually privately and individually owned and can have their own rules.
But most RV parks will certainly allow people to live in their RV and rent the RV space yearly and sometimes you might even get a long term stay discount.
RV parks exists to make money and provide someone with a place to stay so most RV park owners would be glad to keep you their in the RV park year round and make the money.
I've stayed at an RV park for a few years in the same RV park and it was cheaper than renting an apartment.