As mentioned in this question and answer, baloo file extractor often randomly pops up in the background in KDE Plasma, and consumes a lot of CPU cycles.
The answer says that it is safe to disable baloo.
What does baloo do? Will it disable file search/extract features in dolphin if I disable baloo?
Baloo is part of the KDE Plasma desktop. Specifically, it is the file indexing and file search framework for KDE Plasma. Baloo is not an application, but a daemon to index files. Applications can use the Baloo framework to provide file search results. You can learn more about Baloo in the KDE Community Wiki.
Yes, you can safely remove or disable Baloo, but if you intend to search using KDE tools, you probably shouldn't.
As mentioned in the comments, it has been verified by OP that file search in Dolphin works after disabling Baloo, but file search in KRunner does not work anymore.
I'm glad that you linked to this question, because while it has a good top/accepted answer, I have issue with the question itself. The question implies that because the daemon uses background RAM, that the system runs slower, and therefore should be removed. This can become a slippery slope where one might want to start methodically disabling processes to get the RAM usage lower.
In fact, this is counterproductive because the opposite is usually true: daemons that perform tasks like search indexing and caching can dramatically increase the speed of search results when you call for them. There's a saying: "Unused RAM is wasted RAM". Unless your system is starved for RAM, I would not worry about processes using it, and would advise against disabling services for the reason of reducing RAM usage. The same is also generally true for CPU usage if it's happening in the background and not interfering with other processes.