I've seen enough uncompleted estates and empty unsellable new buildings over time to suspect that such property is significantly risky.
Maybe such property is significantly profitable today, but we can't be sure by the time the building is complete.
I suspect it's more likely a simple business decision: the profit doesn't outweigh the risk.
In London, construction companies work hard to avoid the commitment to affordable housing and pay councils bribes to overcome that. Why would they need to pay councils off if this was a profitable option for them?