If you pay at least $300/year for Unity, you are permitted to disable the splash screen. If you do so, it is not at all obvious that your application is based on Unity. If, however, you use Unity's free, "personal" tier, your application may not disable the Unity splash screen. This tier is allowable until your game is making at least $100,000 per year.
The effect of this is that less successful, low budget, and therefore buggier games are much more likely to display the logo then polished games with multiple people working hard and a budget. Thus Unity has accidentally created a licensing scheme which causes gamers to associate them with lower quality games.
Every large AAA Unity game I've ever played has a certain jankyness to it...microstutters, glitchy UI. At some point you just have to accept that the common variable is: Unity.
So you end up with more asset flips, unexperienced devs, etc. on the Unity engine than say the Unreal engine.
Edit: Maybe you could provide a few examples of games with those issues?
Cities Skyline is the poster child (well besides KSP) of Unity Jankiness. Just look at how many mods there to fix basic things in Skyline.
I suspect that KSP is janky because of KSP (or because it was built on a very old Unity and ported over across many engine versions.)
But yeah, AAA games usually have specific requirements better satisfied by a custom engine.
The Unity Pro and Plus subscriptions have no limitations to customization of the Unity Splash Screen.
The Unity Personal subscription has the following limitations:
The Unity Splash Screen cannot be disabled.
The Unity logo cannot be disabled."
I wonder how much the logo displaying has an impact on your perception of the game.https://store.unity.com/ - I think these prices have changed since Unity first appeared.
The abomination that is the Unity launcher: Very much.
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