"All other battle tiers should get a random map distribution, but technical reasons relating to the allocation of server resources cause the three maps above to be the most commonly played maps for all tiers" Which three maps?
Low Tier Camo
Currently the page says:"Important note regarding camouflage skins: All (as of 8.0) of the maps listed above are summer maps. This means that tier 1 tanks and most (see Matchmaking Chart for exceptions) tier 2 tanks/tank destroyers will never see a winter or desert map. So, for now at least, purchasing a winter or desert camo skin for these vehicles is a complete waste."
Winter Himmelsdorf was introduced in Patch 8.11 and was available for lowtier battles (Battletiers 1-3) But it was made unavailable for lowtier battles with Patch 9.2. The reason for this was not given.
Update in Map-selection required
At least in the map-section, this article seems to be pretty old and the new maps should be mentioned too.