The issue is mostly with Paradox and Colossal Order.
They made a promise: " We won't release paid content until the base game is fixed"
They broken a promise " We won't release paid content until the base game is fixed"
CO had no time to fix several key issues with the base game, and while they still focus on that part, they also had no time to fix the DLC they have released. Sadly an unfinished game is a bad foundation for any DLC. Trying to benefit from the XMAS shopping spree with a half baked base game, and a DLC that isn't updated to handle recent fixes to sub building system and feels a bit half baked looks like a rip off, even if the building assets would be otherwise good.
Even if this DLC is mostly about growables, so it isn't influenced by changes to sub building system that much, the foundations are still unstable, and we see "another half baked product so PDX and CO can benefit from the XMAS season".
Currently people trying to combine growables from multiple packs often experience odd looks.
To fix such problems, some scale issues sometimes we might want to filter which growables are possible in an area. if CO would want to fix that part of the game, we would need updates to metadata about all DLC buildings. Not fixing all the issues before releasing a paid DLC can hinder updates to the base game, can make DLC outdated quickly, can create issues on the long run...
Releasing the DLC "early" to benefit from XMAS shopping is an disservice to all the players and fans.