It's always difficult to judge young players from substitute appearances. In a successful team they can be brought on for 20 minutes after a game is virtually won and so it's easier to make a mark. List has been brought on as a last throw of the dice more often than not in a side that has struggled going forward. I don't make massive claims for him but I see more potential than some other posters. He has genuine pace, which is the gold standard, when he applies it intelligently he is effective.
I note that fans judge some players more harshly than others and it strikes me that List gets a harder ride than Nash. Nash came with a single season's form of impressive goalscoring at Maldon & Tiptree in Isthmian League North. He was already older than List is now at the start of that season and has shown little to suggest that he could produce that form at a higher level.