I did some research into this a few months ago, and it turns out you're right.
If a company is serious about learning about its customers and how they use their products, then it invests in Adobe Analytics.
If a company is looking for something that's free, quick, and "good enough," then it goes with Google Analytics.
Just like if a company is serious about advertising, it hires a professional ad agency. If it's looking for something cheap and "good enough," it go with Google AdWords.
For startups there's plenty of options, mixpanel is probably my favorite.
Google Analytics probably has more users because of ease of use for small business but I wouldn't say it's a space without competition.