This is exactly the kind of thing the article is complaining about. You could say "that long load time is going to be bad for productivity", it's a valid critic

This is exactly the kind of thing the article is complaining about. You could say "that long load time is going to be bad for productivity", it's a valid criticism and deserves a response by whoever is explaining the tool. But you don't, you say "that editor sucks". It's aggressively negative language which doesn't even specify a problem. Whoever is recommending this system is likely nervous, and very invested in what people think of it, so you saying "it sucks" will feel like a personal attack. It's completely unnecessary.