I don't mean to pick on you or anything. I think you've written down what a lot of people feel, but it's kind of crazy to expect that of yourself.
It's OK to just be OK.
To each his own, the imporant piece in my opinion is to not judge others by your own measuring stick or live your life trying to measure up to others to get their acceptance or approval.
Every runner practices and runs to win the race. Every fighter also fights to win a championship. I realize a job isn't any of those but when you realize that ultimately a runner and a fighter both run and fight against themsleves, to be the best they can be and nothing more then maybe that is something we can all relate with.
"I'm not better than everyone else but I think I should be" is not impostor syndrome. You don't see yourself as an impostor, wanting to push yourself hard to achieve more is not impostor syndrome.
If you ran a very popular blog and still felt you couldn't write blog posts then that would be impostor syndrome. If you had published a lot of papers and still felt you couldn't make something noteworthy then that would be impostor syndrome. But feeling bad over not being able to do those things when you haven't done them then that isn't impostor syndrome at all.
Be kind to yourself :)
FWIW, I struggle to relate to "competers". I do things because they make me fulfilled (or put food on the table), not to "win" or be the best at something. I don't think it's something everyone can relate to.
This is definitely not true.
Now, this isn't to say that others' opinions don't count. You need some external sanity check to avoid turning into a crackpot smelling your own farts all day. But doing something of substance, and marketing it are two very different things. Blogging and public speaking are useful for the latter, but irrelevant and potentially detrimental to the former if one lacks the proper motivation.
I would say, figure out what you're good at and what your goals are independent of recognition. Learn from experts, and develop self-awareness, but always keep your own barometer of success. If you do this, then whatever recognition that comes will be genuine and you have no reason for imposter syndrome. If recognition does not come, whether because your contributions were mediocre in the grand scheme of things, or because of lack of self-promotion, you can still sleep at night knowing that you made the most of your gifts. The idea of pursuing greatness and global personal competition among 7B people fueled by instantaneous connectivity and social media is absolutely toxic and undermines each individual's ability to follow their own muse and make their own unique contribution.