It would be impossible to determine what monies have been spent in what way. The only thing that is pertinent is that Spurs pay the interest and repay the loan within a year. In other words, you the taxpayer will get your money back with interest. Nothing to see here.
What Spurs have historically earned from their stadium on average isn't at all relevant. They are now in a new stadium that is on an altogether different level in terms of revenue generation. At the new stadium, general admission and corporate sales for Spurs games will now bring in some £100m per annum. Additionally, the stadium is generating a further £500K-£1m per game from food and drink sales.
On top of which, because of the versatility provided by the sliding pitch, the stadium was attracting numerous big events - both sporting and musical. Lastly, the stadium is specifically set up for conferencing and other events. That schedule too was heavily subscribed. I don't know exactly how much of the estimated £200m of lost revenue is attributable to the inability to utilise the stadium but I do know that it is far more than the £85-90m figure that you are suggesting.
Listen, I get that you obviously don't like Spurs. And I get that you don't like the fact that City get a raw deal in the media. But given the extraordinary success that you have enjoyed over the past 10 years or so, the laugh is on them, surely? So why be bitter about the fact that a well run business like Spurs is using a perfectly legal and entirely sensible means of coping with the problems created by COVID19? You're in clover, mate. Enjoy it. I wish we had your problems! ;-)