Diffusing or bouncing a flash is a very common technique for
professionals. Rarely will you see product images that were lit
by direct flash. Also works good for portraits, and even for some
outdoor shots.
You can bounce a flash off of the ceiling, adjacent wall, a piece
of directed lightboard (flat, white styrofoam works great). I generally
prefer bouncing over diffusing, but that's not always possible.
Portrait shooters generally use at least one off-camera speedlight
that is flashing through (or off of) an umbrella. Diffusers come in all
shapes and sizes, from those that attach directly to the speedlight to
stand alone screens and filters.
Back when I was shooting residential properties, I would use as
many as 6 off-camera speedlights, all bouncing their flash, for a
single frame. Much time was spent making sure the
"flash bloom" was never in the image, and this could be very
challenging due to mirrors, windows, etc.
Here's a couple good articles and tutorials:
https://fstoppers.com/bts/simple-tip-mastering-camera-flash-2-min-read-7992
Using Off-camera Flash to Fix Lighting Problems for Outdoor Portraits
How And Why To Diffuse Your On Camera Flash ? PictureCorrect