Probably your software is so inextricably part of your life that the thought of a world (let alone a blog post) without it never occurs to you.
It's a good post. The reason you're getting criticized ("spammy", "self-promoting", etc.) is that it breaks the informal conventions that have evolved for such hybrid (good content plus product promotion) posts. One is to give the reader a clear heads-up that the post falls in both categories.
In the absence of that signal, the flow for me went like this: 1. A blog post about improving productivity? Cool. I like productivity. 2. Hmm, this guy isn't an idiot. Guess I'll keep reading. 3. Some of these points seem useful, I wonder how I could apply them? (In the meantime, completely missing the first mention/link to your product). 4. Further down, dimly noticing the product name, but not thinking about it. 5. Recognizing the third mention of the product - what's that? Seems vaguely familiar. 6. Finally: oh, I get it. This is software he's selling and the whole post has (also) been about this. 7. I feel like a bit of a dupe. No like. Bail.
The only reason why 7 occurred is that the post didn't set my expectation correctly at the start, so I read it with a wrong expectation, then had the unpleasant experience of reality contradicting it. It's actually the fact that the content was good enough to absorb my attention that led to this; otherwise I would have noticed the other details right away.
