I've found the more senior I get, the less spurts of productivity are tolerated. People will rattle on about consistency and expectations. Especially so if this is more on the scale of weeks than within a day.

I can easily be productive when I am working with people on business problems. But, for coding, I need time to get in the zone.

In contrast to your case, the managers in our team do not do any coding at all. I imagine you are talking particularly about senior ICs.

Yes. If you're a senior IC and tend to do several days work on your good days but get little done on your bad days, depending on the boss you have this can cause a lot of friction (even if overall you're producing a lot).

There's a strong tendency to "watermark" your productivity, and ignore circumstances around it.

Today is a perfect example, I got to look at code only for the first hour before I got a pinged about an issue somebody thought was related to code pushed out last week. It turned out the issue had nothing to do with it, but I had to investigate that. Then I got pulled into a conversation about why a certain number was up and how we might ameliorate that; came up with a pretty simple solution someone else is implementing... but then I got asked if I still was working on some low priority ticket so I had to figure out what that was, and then my boss wanted more details in our weekly status update so I had to search up some docs and tickets and stick them in there. Right now I have 15 minutes between lunch and a meeting with HR, and no, I'm not using it productively - because how far can I really get in such a small time window?

I budget for this reality in my estimates, but often get pushback. "Is this really going to take a week?" Well, no, it's not. If all this crap was pushed out of the way it could get done in a couple days, like project X did. But the reality is I'm halfway through my workday and had at best an hour to code uninterrupted - much of which I spent checking my email and doing code reviews because I often get tagged for not doing those things often enough

There are quiet days when I can just code, and there are days like this. And even in the former category, not everything is perfect; sometimes I didn't sleep well or have other personal stuff. But the days everything went well sets the expectations, while the reality is much less predictable.

“It’s going to take a week for the org to let me spend two half-days on it.”

If you've got Outlook or some other calendaring tool, fill it in with each external request when you get done with each one... when performance is questioned, you can review the history and hopefully get a more reasonable, "oh, I see" level response.