Recursively searching through all files in the current folder (aka the normal use case for grep) is accomplished by using "grep -r". It's on line 270 in "man grep". And that assumes that you know what grep is at all. Would it have hurt so much to call grep "regexsearch" instead? Maybe -r could be the default?
Recursion is caused either by -R or -r on nearly all commands and is pretty standard, and r is virtually never the default on any command because that would be a bad idea. And yes, having to type regexsearch rather than grep would have been a bad idea; while grep isn't a great name it's far preferable to someone who types constantly. Search or find would have been better names, names need to be both short and descriptive on the command line, and short comes first.
$ man grep | grep recursive
directory, recursively, following symbolic links only if they
Exclude directories matching the pattern DIR from recursive
-r, --recursive
Read all files under each directory, recursively, following
-R, --dereference-recursive
Read all files under each directory, recursively. Follow all