No, I'd disagree.

The word resort attached to a hotel is to give a description of the hotel / location etc. Seems a fair description for the hotel the OP mentions. Being a resort doesn't mean every resort facility needs to be open 365 days a year.

You are then confusing the naming of a hotel as a 'resort' with the SPG program definition of whether a hotel is a resort or not. That has relevance from the perspective of the T&Cs of the program as to whether it has the right not to offer 4pm check-out for example.

I can see nothing wrong with a hotel that is marketed as a resort, but is not flagged as a resort within the SPG program, or would you prefer that every hotel with the resort name has the right not to honour 4pm check-out? Likewise, a hotel that doesn't use resort in their title can reasonably be flagged as a resort within the SPG program. If it is, it will be clearly listed in the program T&Cs for SPG members.

As for the dictionary definition of resort, it is "a place to which many people go for recreation, rest, etc". So unless you can prove that a property only has a business customer base and has nobody going there for recreation or a rest, then I'm struggling to see how a property or SPG is misleading anyone.