Alright just seen the vid.
Basically..
1. 'Freak' mistakes -- what the hell! rubbish revisionism.
2. Contract - so? we're kicking out Sanchez out on loan and making him feel unwanted here, until he eventually leave the sooner the better. Rooney's contract also once expensive, and he left.
3. Age - yeah not a prime age for keeper, VDS also made mistakes before when younger. Some keeper will manage to shade it out, some don't. It's a risk continue persisting with him, seeing how we have one younger keeper knocking on the door. Afraid of dare to take risk, a good calculated risk at that will lead to stagnation. Many examples of top teams changed their main keepers quickly and get better results eg. Real with Casillas, City with uhh the keeper, Chelsea with Cech, Pool with legendary Karius (he's their main), we also spent time immediately trying out different keepers after Barthez cost us too many games (he was that good before mind) , etc.
4. Loyalty - lame weak reason. Eg. Rooney. We should've keep him longer then. If a player (doesn't matter loyal or not) is past it or making more and more costly mistakes to the squad... "Thanks for your loyalty and away you go!". De Gea's "loyalty" i.e. staying is also easier when his wages is generously bumped high and higher each time. He always wanted to leave, bear in mind that.
5. Who can replace him? - Henderson, stats and performances this season showed he is roughly the same with De Gea's performances. So what if De Gea of before are godlike and far better than Henderson of this season, De Gea is no longer that player. Henderson + Romero as back-up. Our defense have also improved than before so risking slightly with a new keeper would be fine.
Exactly!