Pretty much all video games use UDP.
Pretty much all video games use UDP.
Generally speaking when you have an interactive session with > 1 parties (especially humans) when/if packet loss or out of order packets occur there's no reason to attempt re-transmission because the clock, people, and application continually move forward in time. Consider a VoIP call - by the time a packet is retransmitted the conversation has moved on. Most audio codecs and implementations have a default packetization interval of 20ms of audio per packet so this is pretty granular.
This has been mitigated somewhat with audio codecs like Opus that have packet loss concealment and forward error correction techniques that provide relatively high robustness to this issue. Variable latency (jitter) and out-of-order packets are typically handled by dynamic jitter buffers on each receiving side that can detect when the finely-clocked streams are wobbling. They then buffer incoming frames, potentially with re-ordering, and play them out smoothly with the side-effect being slightly higher latency to perform this (that's why they're dynamic).
Loosing a few pixels or missing some object updates won't be noticable in high fps games, but where correctness and completeness of data is needed, UDP based applications end up implementing TCP features in application layer.
These application layer implementations can be more performant (low latency and/or high throughput) with UDP, utilizing the special cases, than TCP, which needs to provide generic facilities to every application running on the same host. And then it becomes a question of available resources vs benefits.
Example: DNS started as UDP and later used TCP when expectations on correctness grew.
That said, We have high capacity and high quality backbones that UDP looks right choice for many cases, and should be used where it makes sense.
Initially for domain transfers, and now for DNSSec etc where you can get rather large certificates embedded.
Also it's rather handy if you're tunneling over a proxy that only supports TCP ;)
But it's not the only reason to use UDP. It can open connections faster, accept out of order packets and generally offers a low overhead datagrams for building custom protocols.