Spurs could be in a really tough spot this summer. Madrid might be looking for a manager, PSG definitely will be, and Pochettino is rumored to be on the shortlist for both. If he leaves we know Rose wants out, Alderweireld won't sign a new deal so he could get sold, and who knows who else there is in that squad who's had enough. And then of course where does that leave them with Kane? Can't imagine he'd be jumping at that point to sign away the best years of his career to a borderline top four side.
Their system is a house of cards. You can't systematically pay your best players way below market value, not win anything of note, and expect them to stick around when they could jump ship, double their salaries, and have a better chance of winning things. Judging by the reporting, the players took notice of Walker's deal, and the results for him have been self-evident. Once one or two more make way the whole thing could come down.