Let me ask you instead, how much do you think does a clan farm with 55 ppl? out of curiosity.
so as it was stated in chat before ptr was restartet, i stick with 55 clan size example. so 5mio by 55 members that makes 90k per player, with your average player having up to 10 mio that seems not really that much. or do you plan to own a building alone? then try that and see the pricing is a lot lower.
How long does it take to farm those 90k dds? I would say on average it may take an hour (depending on the usage of boosters, types of mobs hunted and experience). So now, all those 55 players have to hunt for a whole hour just to upgrade a single site once. A single site is not enough for all 55 players. Additionally they still have to hunt dds to teleport around the map during the attack phase. Depending on its length, each player will spend at least another 100k dds. Not to mention the auctions, upgrades, clothes that all require huge amounts of dd.
Any player that is not able to hunt hundreds of thousands of dds daily will risk getting kicked from their clan. They do not provide enough resources to justify the cost increase. People will look at it this purely economical way, especially when it comes to strangers online.
Many veteran players, original clan creators, old friends may also get kicked from their clans simply because of that fact. They will become "dead weight" for a clan. Each new low lvl player will also be considered as dead weight, as he cannot provide additional dds for a long time while he upgrades.
That describes the first possible outcome that I see if those numbers don't change on the live servers. Players will be forced to abandon their large clans and split into small groups. A sense of community will be harder to maintain with time.
The other possible outcome is that this upgrade feature will not see any major use. Players will forget about it, and it will only be used rarely when gates get taken over by a small group. However even that small group will likely not use that feature much - the yield increase has to be very significant to justify spending a significant amount of dds on it.