Why don't more people use Raspberry pi as alternative to LiveU solo (for IRL streams)?

I've seen lots of tutorials which outline how to build an IRL backpack/gunrun setup. The easiest (but most expensive) option is to use a LiveU solo ofcourse, but the tutorials also outline that a raspberry pi 4 can be used to replace the LiveU. But all the IRL streamers I see use the LiveU, if anything at all. Why don't more use the Raspberry pi 4? Has anyone tried it and can comment on how it compares to the LiveU? thanks!