The timing of this closure has everything to do with the internal pressures I mentioned and nothing to do with the external pressures such as Microsoft. Were Microsoft not placing any pressure on BuildFeed, I doubt there'd be an issue, but it's also true that had I not made some mistakes in the past, there would be little to no internal pressures and we wouldn't be looking to close either.
The key here is to ask regularly rather than just once or twice. Most of your followers only see a fraction of your posts, and you should be getting new followers every day, so it makes sense to request subscriptions at regular intervals. If you can offer some sort of incentive or even just promise exclusive content within your emails, that helps too.