[foobazgt]

He doesn't just say "why is this so hard?". He provides rationale for what he thinks is required and the effort it should take, posits some things he might have missed, and asks for more explanation. If you get a good-faith request like this from a technical manager, you should be able to point them at some docs or give a relatively concise response as to what they're missing. Honestly, you should have already headed this off, because the moment you realized you were in danger of missing deadlines, you should already be raising it as an issue and either explaining your plan or asking advice for how to get back on track.

If you're missing deadlines, you can't both complain a) when there's no accountability and the business is going poorly, and b) when your managers are trying to hold you accountable.

Ultimately your employer has to make money to pay you for your work. Keeping this in mind is one way to help you avoid yak-shaving, bike-shedding, and other weed-entering activities.