If you have a "choice" of one ISP it's because your local Franchise Authority (your town/village/city board usually) has opted to only grant a franchise to one company.
Wrong. It is because of economics. There simply isn't enough business available to support a competitive set of ISPs where I live. I live in a town with about 10,000 residents on the distant outskirts of a major metro area. There is zero chance that any new ISP would be able to win enough business to make the investment worth their while.
I have a phone company and a cable company both of which could offer service to my residence but do not offer equivalent service. The phone company technically provides DSL service to near me but it is FAR slower and economically a non-starter. The only other option is to go LTE through the mobile phone providers but due to data caps that too is an economic non-starter. It's just not competitive at all and there is no reasonable prospect of it becoming so no matter what my local government does.
Even if my locality were to invite every ISP in the world to come play the simple fact is that in the semi-rural area where I live there isn't enough business to support more than one or two lines to my house. Since the government does not require the ISP to be separate from the company providing the wire to the house then there is effectively no way for any new entrants to make money. The capital costs of building out their own network are astronomical so there has to be a pretty substantial company backing it and enough business they can capture to make it worth their while.
Don't blame the ISP for your local politicians' inability to stand up for you.
I don't. The economics of the situation are plain and a regulated monopoly will get me better service than any feasible set of competitors where I live. The best case I could realistically hope for is a duopoly which isn't a prospect to get excited about.