Google Analytics tells you more about your audience because it stalks people across the web. Matomo can never provide that without having a broad range of websites from which you collect data and writing custom code to annotate visitors with your own interest tags.
Matomo purely tracks analytics: who visited what page, for how long, from what device, from what location, from what inbound website, and what outbound links did they click. It also provides a log of pages requested per session so you can analyze people's flows through your website.
It's certainly not a replacement for Google Analytics if you use it to collect background information on your visitors. Even though Google's information is very broad (you mostly get ranges and the interests aren't that reliable), some marketeers use it to make decisions about their marketing strategies. Matomo won't help you there, your alternative would probably be Facebook or another big tech tracking solution.
It does provide a replacement for the type of tracking that I personally find acceptable, assuming the IP addresses are anonymized sufficiently. Matomo recommends shortening IP addresses to /16 after analysis, which I consider good enough, but that's a setting administrators can change.