Show-stopper for me. I have no need to retrain my coding habits, there are plenty of computer companies that still happily provide the ESC key as they have for the last 30 years, so I'll just move to one of those computer brands.
Is your main gripe that the esc key is no longer a physical key? Or that learning a new placement of the esc key is difficult to adjust to?
But to your point, there are many ways I could workaround this change (changing key mappings, for example). But my point is; I don't have to. There are plenty of companies willing to sell me a computer with the same keyboard layout that's been standard for the last 30 years. I'll just buy one of those.
I see this no different than any other product I use on a daily basis; I would be resistant to change if it aversely affected my use. Luckily, I don't need to change my habits to conform to Apple's latest bravery. Apple needs to know this; they don't own their customers.