I'll stand by my position that any strategy that leads you to victory is a valid one. This doesn't mean I have fun playing against every single deck, but even if I don't enjoy watching my opponent play Solitary, it still a valid strategy. In that sense, I agree with XK9.
That said, I really don't like donk decks after all xd It's not unfair, but it's completely non-interactive. If your opponent pulls the donk, you lose before you can do anything. If they don't get the donk, they auto-lose because those decks are terrible if they can't FTK you, so there's not much for you to do anyway if you survive the donk. Tbh, I don't even know if it's efficient to play donk decks on the ladder anymore. To me at least, it seems more profitable to play a good, consistent deck that can get you some good winstreaks going. Playing donk decks is probably even less than a 50/50, since you have to go first (most people won't make you go first when they win the coin flip), and even then, if they bench some pokemon you can't don't either. It's true all your games will be fast, but the way I see it, you're doomed to earn 10 points at a time, when you could otherwise be earning 30-40 points in a single game if you keep a winstreak going.
TL;DR, I dislike donk decks, but I don't think they're a problem. It's a legit strategy so it is what it is.
About netdecking, I don't think that's a problem either. A while ago a guy came claiming that it's "negative player experience", but never came back to check on his own thread after he found no support. There really is nothing wrong with people taking another person's deck and trying it out. If they want to succeed at it they'll have to come up with their own variation anyway. Then there's also the fact that it helps new players that don't have any experience or knowledge to build an "original deck", so going with something well known and tested is a much better choice.
You're not really just "following a recipe" and riding it to victory either. Adapting to each individual situation and consistently winning against many different decks, including the ones that counter you, takes a lot of knowledge, experience and it also takes skill. If I insisted on discarding everything turn 1 on Night March to attack for 190 damage even against Trevenant, Toad and Night March mirror matches, I would lose just about all of those games. Being flexible with the exact composition of your deck and being able to adapt to the conditions of each game is harder than repeating the exact same recipe every time. Knowing the weaknesses of your own deck, teching out your deck correctly, choosing a proportion of cards that will carry you through as many different situations as possible without bricking your deck, all of those are more complex and "copy the deck --> spam it and win".
Now, I can't give you a very objective opinion on Night March since that's literally the only deck I play, but I don't think you're right on calling it a "turn 1" deck. Turn 1 is just the big setup, but you can hardly say you've won or lost the game on the first turn as Night March, and honestly, if as the Night March player you think you won turn 1 because you attacked for 190 damage you are gravely mistaken. For all you know, your opponent will bring out an Oricorio next turn and KO all your pokemon simultaneously. Or, if you carelessly spend your 4 Battle Compressors turn 1 and your opponent gives you the old one-two punch with Lele into Karen, you're pretty much donezo. If your deck usually loses hard to Night March, it on you to play at least 1 tech card that counters Night March, and if you don't that's simply your own fault there's no excuse to not run at least a single Oricorio in your deck. You don't even need to attach energy, use their own Dimension Valley against them and attack with 0 energies. You'll pretty much never see a NM deck use Karen themselves, so if they discard 9+ Pokemon it's a done deal, there's nothing they can do to stop you from taking 2-3 KOs a turn.
So yeah, games against NM are hardly over on the first turn even if they manage to go second and discard 9+ Pokemon right off the bat.