Oh no, an Anon is trying to do something productive! Let's dogpile him, quickly!
>>15998254
Don't use XNA, it's dead. Instead, use MonoGame if you want to use C#, libGDX if you want to use Java (before you >Java, it's just a less featureful C#), LÖVE if you want to use Lua, Phaser for JavaScript (and before you >JavaScript, Cross Code is written in JavaScript and it's correctly performant; fuck, even 3D works well in JavaScript nowadays), PyGame for Python even though I don't recommend it due to its ass backwardness, SDL for C if you want to be a /tech/ LARPer, or whatever game libraries are available for your meme language of choice.
Using Unity is "okay", though. The engine is shit, requires you to rewrite as much stuff as building your own engine using game libraries, some behaviour os hardcoded so you need to buy the source code license to modify it (worst offender is the asynchronous level loader, which isn't very asynchronous) doesn't work all that well in GNU/Linux builds, has shit controller support, the UI may be overkill for 2D, the executables may be a few MB bigger than with custom solutions (which won't be all that low, considering you are not a demoscener), shit modding capabilities, eventual editor crashes, etc., but all performant 2D nowadays is just ortographic 3D. Software rendering is slow as balls, and basic graphic libraries (OpenGL, DirectX) all work with 3D.