Nope - the newest lines (Victoria, Jubilee) are all smaller diameter trains. The larger, squarer cut+covers (District, Circle, Metropolitan etc) are generally older, because you can't cut a trench across London for a new Tube line any more.
It's still not hard to stand on any of the trains as long as you're not right beside the door on a Tube (unless you're extremely unusually tall, but the odds are well against that).
It's still not hard to stand on any of the trains as long as you're not right beside the door on a Tube (unless you're extremely unusually tall, but the odds are well against that).