I didn't say that at all. I'm assuming you know about counter picking, but in case you don't I suggest you look it up. Picking an old mid against a current high burst mid laner is countering yourself. Normally you try to counter someone else, but there are some situations where you actually want to counter pick yourself.
Now, when you are not against a high burst assassin style mid laner the old mids are completely fine, and scale very well into the late game when played correctly. You just need either a favorable matchup to come along or enough personal skill to make it work anyway.
The key thing to remember is that a meta shift toward one play style does not make the play style it counters unviable. Assassins do well against mages, where as mages do well against other things, and if you're unwilling to adapt to what is currently popular you'd best be stubborn as hell.