This is actually a very reasonable response, if only delivered in a somewhat dismissive way. I believe the point is that even if you follow the recommendations

This is actually a very reasonable response, if only delivered in a somewhat dismissive way. I believe the point is that even if you follow the recommendations to the letter, and do everything correctly and never even accidentally change API behaviour between minor versions, anyone using your product still cannot be sure that that is actually the case. When I upgrade a piece of software, can I rely on the version number actually reflecting the compatibility? Of course not. As long as even a minority of software doesn't follow these recommendations (and to be realistic, they never will) you can never actually rely on these numbers for anything useful in the general case. In the special case, sure. Some vendors have very strict compatibility guarantees and that is really useful. But to take advantage of these guarantees you need to read their documentation on the topic, and if you read the documentation it doesn't really matter what versioning scheme they follow.