Ask your drafters about it after the game, they don't end up equivalent.
I'm confident that if I asked any drafter after every game that they missed on Glint-Nest Crane whether they'd prefer to swap it out for a Seacoast Drake, they'd say no. It seems absurd to me to argue that you might not want a card in the cube because it doesn't have its best case scenario 100% of the time.
I you make one card better, then you are indirectly making all other cards worse. It doesn’t matter if the card is a lot or a little better. That is a choice and it is an argument against not always picking the best card for the cube. The other option is power max.
This is also completely reductive and demonstrably untrue in this specific case. Adding a Glint-Nest Crane to your cube over a Seacoast Drake makes every artifact in your cube better, not worse. I will concede that it raises the average power level and therefore some cards will be lower relative to the average power level, but in that case it does matter whether that's by a lot or a little bit. You might be ok with raising the average power level 1% but not 10%.