Previously at Voobly, team ratings where lower than 1v1 ratings.
Top 1v1 was around 2.7k, while top teamgame was around 2.1k.
DE has a completely different system. You can win/lose much more points with team games than at voobly. On the other hand you start at 1000 Elo at DE, while you started at 1600 at Voobly.
Statements like ‘2600 has been the roof since its beginning’ is clearly not true. If we still would play at Voobly, you will als have 1v1 ratings of 3000 over a while. The ratings of top players did also increase over time.
I do feel team game ratings are off in general, but i dont think your point is really part of it. I made my own thread about the ratings a while ago. Have a look: