The professional users will pay for the software they're using, or accept the consequences of the tech decisions they made. Maybe the release wording sucked, but software vendors shouldn't be on the hook to sell you the thing you already bought.
You weren't "forced into non-compliance", you could keep your hot dog (=caddy executable you downloaded before) just fine.
The difference between hot dogs and software is that hot dogs don't get (and don't require) updates after the fact, while for software they are important.
EDIT: also, you don't accidentally install new hot dogs through dockerfiles or something - it's quite possible people ran into non-compliance that way, given there was no prior warning.
> Beginning today, all official Caddy binaries come with an End User License Agreement (EULA) that designates them either for Personal (non-commercial) or Commercial use.
They probably could have clarified this by saying "Beginning with version 0.10.9" instead of "all binaries".
IMO the author doesn't realize how much price factors into tech stack decisions, or how the majority of his users are developers who now have the new responsibility of creating business cases for a piece of software (or scramble to find a replacement) that need to go through approval, or the projects that now have to be delayed to switch around one framework on the back end (I can just see the looks of manager/PM faces everywhere when they get the news from one of their devs).
The tone is another big issue. Flippant phrases like "what's new for personal edition users? Not much" isn't going to get any laughs after talking about mandatory payment. Other times, the disdain for users seeps from the wording (like the passive-aggressive "reminder" that internal apps constitute commercial use).
I'd really encourage the author to go back and re-read that announcement as a user who has taken a gamble on your software and is now invested in it. Yes, this might be a completely necessary move for the survival of Caddy. The necessity, though, doesn't mean you can skip the formalities. Users still need to be sold on the idea.