What can I do to update this 1980s bathroom?

Paint the walls and lay ceramic tile floors .

lightly sand,clean,and prime the cabinets,paint and seal with a non-yellowing polycrylic.As for paint colors that is truly personal. I would choose a natural color and use colored towels ,carpeting and decorative accessories for the color.

Paint it all...vanity, walls, window, etc. Maybe some floating shelves over the toilet. Neutral colors that work with your tiles. Use accent pieces for pops of color on your shelves and countertop

I had a bathroom similar to yours, and found painting the walls a light gray and the cabinets a darker gray made a huge difference. A new shower and window curtain and new towels made a whole new room. I changed our mirror, too.

Go with what Cynthia said. Gray is the new beige. Buy beautiful towels to coordinate.

How about if you paint the walls first in a light color, maybe a very pale beige or even a light, light bluish grey and then see how it looks with the cabinets in the color they are today. Change the floor to a less busy pattern (I'd go with ceramic tile). Buy new accesories, towerls and rugs in complimentary colors and use a visually appealing shower curtain. This might do the trick without having to paint the cabinets.

Paint the cabinet's and change out fixtures will give you a completely new bathroom.

And it looks like you have tile board in the shower behind your shower head, faucets and water spout. I would get one that matches the other side better, or tile that wall to match the other 2 sides. You could repaint the whole thing with Rustoleum Tub & Tile paint for a fresh bright clean look.

Grocery Outlet has some of the best prices on bathroom rugs, shower curtains, mats and towels. and their good quality. I've been buying them there for disabled clients for years.

clean thoroughly and paint, change newer handles on drawers and doors, new shower curtain and towels