When I test for Champs, I do a ton of playtesting. Most of my testing goes into swapping around cards that improve one matchup at the expense of another. I played as few as 2 missteps, balance, ancient grudges in the main, and a huge variety of creatures. When I test I keep track of my winrate against various archetypes and look at my prediction for the expected metagame.
The deck I played at Champs had 4 missteps and 0 grudges in the maindeck. The reason was that I could not consistently beat delver, which both had a high metagame representation online and I expected to be well represented at Champs. Sitting on the pulpit and telling blue players how they should be building decks strikes me as assuming that the deck that one arrives at was without proper testing.
In my 10 rounds at Champs I played 1 dredge, 1 shops, 1 mono red deck, and 7 blue decks. Perhaps a more expected result would be 2 shops decks, but I can't understand how anyone thinks I am going to improve my 8-2 record (losing to dredge with 8 sideboard cards and mono red) by cutting missteps and switching my abrade for an ancient grudge in the maindeck.
We don't get to engineer the metagame for a tournament. I can't force 50% of room to be on shops. I can't, as Matt also alluded to, make a pact with the other blue players not to play misstep. If you want to play blue and want to maximize your overall winrate you need to construct your deck in a certain way. If misstep gets restricted I am not replacing them with 3 grudges; likely they become flusterstorms, mindbreak traps, or pyroblasts. If someone can build a blue deck that has a decent winrate against the 70% of the meta that is blue and consistently beats shops, then sign me up. If such a deck exists, however, it would have an incredible winrate and unbalanced.
Just to be clear I do agree with several points in the article. I think we should give the metagame some time to sort itself out (look at the crazy metagame online right now). The "reusable black lotus" line doesn't hold water when you can't use your lotus to cast ancestral recall. The constant complaining about B&R is incredibly annoying and frankly toxic to the community when every conversation devolves into that.