Absolutely not, as the £850m cost was being quoted back in 2017Thanks. So it did shoot up at the end.
https://www.mirror.co.uk/sport/football/news/stunning-new-pictures-show-tottenhams-11720081
It's just the Mail and Standard decided to keep saying we'd gone over budget (when we hadn't) while also quoting completely misleading costs, which I'm sure has nothing to do with the latter being edited by a Chelsea fan and the former historically agreeing with the bloke responsible for the Holocaust so they might have problems with a club noted for its Jewish fanbase...