There are no Starships, and no specific way they're "supposed" to work. Every game has its own internal logic, and conforms to such.
The EVE comparison is also sprurious. Every ship in EVE is better or worse suited to certain kinds of behavior. You won't see a frigate doing the job of a battlecruiser, or a Titan doing recon.
The difference between EVE and STO (and there are very many) is that EVE has a LOT of ships and a much more modular (and much more complex) system of customization and character/ship specialization. Ships may take a number of roles within their class, but will never perform every role, no matter how customized they are.
In fact, in a way STO is even more "multi-role" than you claim, because every ship in the game can perform every mission in the game, no matter its class. A Defiant escort can perform a science quest, or explore strange new worlds or what have you. If it was as bad as you say, certain missions would be restricted by ship type. Escorts would be banned from doing cluster exploration missions and science vessels would be banned from STFs.
Instead, while every ship in STO has a speciality determined by their build possiblities and stats, they can all do most of what's asked of them by Starfleet/KDF.
Is it a "for dummies" interpretation of Starship operation (whatever that means)? Probably, but if it weren't, the game would simply not be fun to play for a huge number of players (the ones who can't handle EVE among them).
i think star trek is more based around real world warships then eve diffrent size for diffrent jobs e,g u did not get battleships chaseing down small 10 men craft thats wot potrol ships are for.
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