Why Small Studios Still Default to Unity, and Big-Budget Teams Default to Unreal
One is a fully-equipped rental kitchen you can start cooking in today; the other is a custom-built kitchen that needs a bigger staff to get the most out of — neither choice is wrong, they're sized for different jobs.
A small restaurant just starting out often rents space in an already fully-equipped commercial kitchen rather than building one from scratch — lower upfront cost, everything already working, and a much faster path to actually cooking something. A larger, established restaurant with real capital behind it is more likely to build its own custom kitchen, sized and equipped exactly for its specific menu, because it has the staff and budget to make that custom investment pay off. Unity and Unreal Engine map onto roughly that same split for game studios choosing where to build.
Unity's appeal to a small team is almost entirely about lowering the cost of getting started: a lighter engine, a shorter learning curve, and — as covered elsewhere in this category — a genuinely enormous library of pre-built assets, plugins, and tutorials that lets a small team avoid building common functionality from scratch. For a studio without the headcount to spend months on infrastructure before touching actual gameplay, that head start matters enormously, which is a large part of why Unity still holds roughly 48% of the mobile market, where small and mid-size teams are especially common.
Unreal Engine's appeal runs the opposite direction: extremely high-fidelity rendering and large-scale 3D environments available largely out of the box, at the cost of a heavier, more complex tool that rewards a bigger, more specialized team able to actually take advantage of everything it offers. A small team can absolutely build in Unreal, but a large, well-funded studio is far more likely to extract Unreal's full value, which tracks with Unreal's roughly 31% share of Steam revenue concentrating specifically in higher-budget titles.
Neither engine is simply "better" in the abstract — the actual right choice depends entirely on team size, budget, and target platform, which is exactly why both engines keep growing rather than one displacing the other: they're increasingly sized for different jobs, not competing head-to-head for the same one.