Breakout is a great candidate for a toy game. As is snake. I often make Breakout clones to familiarise myself with new systems.
If you're looking to get things done fast I think Unity is an excellent choice. After coming from years of working with custom engines and Frostbite, Unity feels like such a breeze.
As for r/gamedev I'm quite active there myself and while I like it and it's gotten a lot better recently it still has an issue where it's largely hobbyists and inexperienced indie developers. Their uninformed opinion will often drown out more qualified voices. So take information there with a grain of salt.
The engine and language does not matter for this first game. The only thing that matters is completing one small game.
After that, you'll have the level of knowledge to make somewhat informed choices about project #2, where you can expand and innovate. You can use hobbyist engines like Godot and have more control, or more professional engines like Unity or Unreal if you want access to those tools and asset libraries.
/r/gamedev has a useful article: https://www.reddit.com/r/gamedev/wiki/faq#wiki_getting_start...