No, no they're not.
It's not about "seperate fecking positions" and your pointless angst towards "the FM kids".
It's about defining or understanding the various roles players have in a football team and differentiating between them. It's about appreciating that different footballers are, in fact, different and despite them a lot of them playing in one giant area of the pitch (midfield), acknowledging that their actual use can be very different.
The whole bit about "can't leave centre circles" and so on and so forth is something I don't think anyone actually thinks and you've probably just made up to attack your age old nemesis - "the FM kid". I'm sure everyone would love their central midfielder to bomb forward, attacking midfielder to help out in deeper areas, striker to press and centre back to carry the ball out of defence, but that doesn't make the use of these "tags" bad. You can both believe in players being flexible and understand their roles being different.
Basically, this is a typical caf argument of going to extremes, with your extreme being "they're all the fecking same! they're all midfielders! Whats an AM, whats a DM, they're all CM's!!". Which, IMO, is over simplistic in nature and overlooks the fact that there are relevant differences between those footballers you want to lump into the same brackets that actually affects their use in different positions.