Did you get any sales on your games? I was under the assumption that you cannot compete with studios in this space, especially if you develop an indie style (solo developer). I read a couple of success stories but they did not get a substantial amount of money despite developing a solid game for months.
There are also well-known cases like Minecraft and Stardust Valley, but that was years of work for experienced people. Quite risky to develop something for years without validating this game idea first, and games are especially hard to validate on the market.
I developed those for fun, not with the intention to generate revenue.
Of course you can. You'll sure as hell not design an AAA title. But a lot of these really popular mobile games can _easily_ be done by just one developer. But _marketing_ them...that's a whole other topic. And you can team up with a publisher for that.
One of the most often posted (and correct) criticisms about behavior in "creative industries" and why people fail to make money in them is because people might be great creative artists, but shitty business people.
When you're just starting out in game development, I'd not advise you to take on games that'll take you years to develop. Start small. Flappy Bird, for example, was a huge hit. And is extreeeemely simple to code.
Before you think about "validating your game ideas", you should "validate your motivation to create games".
What really turned me off most was that the last 10% usually take up 90% of work. It really is that bad. It's nitty-gritty tedious bug-fixing.