Kane is so much better than Mbappe but Mbappe went to PSG and Kane is so much better than Lewandoski who went to Bayern Munich and so much better than Salah who went to Liverpool and won 100 trophies between them.
Kane at 28 was free to stay at a failing Spurs side his whole career and no big club ever showed interest.
You call it loyalty, I call it lack of options.
Indeed it is apparent that no top club has come in for Harry. However, which club needed him over that past 4 years?
PSG - Neymar/Mbappe
Real - Benzema already knocking in 30 per season
City - Aguero
Juventus - Ronaldo
United - Ibra/Martial/.Rashford
Munich - Lawandowski
Barca - Messi/Suarez
Arguably he would have improved some of those squads (united in particular) but were any of them willing or able to rebuild build their squad around Harry?