If what you are saying is true, then AoE2:De, even tho only having ~8% of their playerbase based on the Windows Store, is still more “populated/popular”, than the 35% playerbase of AoE4.
Comparing steam server numbers, AoE4 has more than 1/3 less active users per day (24 hour peak) than AoE2:DE with an 8.000 player difference!
(~13k AoE4 vs ~21k AoE2).
Keep in mind that AoE4 should have a slight playerdrain right now since the ranked beta client is splitting up the community.
Shouldn’t make any difference for now tho, since the game peaks out consistently at ~13k for the past 2-3 weeks.