TWI,
He wins as he manages the game better than you, and he has better shots and overall skill level.
You get some points from your athleticism that surprises him. but most of the match, you pissed away points like old beer and made his job very easy.
On serve receive, throughout the match, you tried some very over-aggressive, poor biomechanic form low percentage rip returns - you missed nearly every one of them. Until you learn to see the ball better (the spin and its bounce - AND use a shorter stroke) you will continue to needlessly give away precious points on receive. I am not saying pushing, but be SMARTER and more tactically intelligent about your receives.
So, if one does not attack, what can one do? A lot. If you change location on pushes and push deep primarily to where opponent will begin to piss away points, that is better. Look at what you did at 24:38 of the vid late in game 4... even though your return quality was very poor (high, not very spinny) the placement was golden. Opponent was slow like Snorlax to move around the ball - have attacked and missed horribly - he gave you a free point... and you didn't have to work very hard for it.
This kind of seeing what opponent does and not does is important, so is noticing foot position and tendencies.
Your opening topspin is not very good quality - you do not whip very well or at least not very consistently in a match. You commit, but are out of time, off zone, or too stiff. You gave away so many points this way. Still, some of your topspins showed you can do it. Look at 15:42 - you move to position, stop, stay loose, and explode upwards and forward - result was a quality topspin that won you the point. You step around and topspin shot emphasizing spin was also successful, even if it was off balance out of zone.
I believe your coach is telling you the right way (rather AN EFFECTIIVE way - there is no ONE right way) He emphasizes spin production and consistency/placement. That is very important at your level.
As for seeing results in a match... not everything you do will show up in a match right away, it can take many months for it to show and be productive in a match.
However, the ability to read an opponent's game, make sound tactical choices, and learn what things to adjust during a match can be applied almost immediately with good effect.
You showed some of that, but not enough vs this opponent. You showed us, that although the opponent is better in almost every way (as measured by strokes and sequences), you showed us that some fight and some wise play can affect this opponent. The times you played it to cause opponent to go for low percentage, you turned the tables on him.