Fun fact: Strawberry is called an accessory fruit because its seeds are on the outside, so the seeds themselves are the real “fruits” (in the same way each grain of rice or wheat is itself a fruit, well technically the fruit consists of the grain plus the outer pod/husk that gets removed when harvested). The red flesh we like to eat is the accessory fruit because it in itself does not contain seeds.

Raspberries and blackberries are called aggregate fruits because they’re essentially many fruits attached together as a single structure. Actually, a strawberry is called an aggregate accessory fruit because it has many “fruits” directly attached to an accessory structure.

The thing is that the botanical definition of berries doesn’t match perfectly with the everyday definition. That doesn’t make the latter wrong, it just has other applications