But how far did Spurs get into negotiating with Sevilla though? If they already got rejected by Kounde first, then the point about Spurs wouldn't have come close to his release clause is kinda moot.
But even if that's not the case, someone else here mentioned that Spurs wanted to throw in Davinson Sanchez into the deal and his market value is €32 million (if one takes the transfermarkt evaluation).
That may be true but one could also argue that there's a big difference between having a €50 million release clause and €80 million release clause. The €30 million difference is a lot, especially if Sevilla are really struggling with the finances and knowing that we're rich and all, they would want to try and squeeze out as much money out of us as possible.