What is the opinion of Reddit about the
Merax High Back PU Leather Metal Frame Swivel Office Chair (Red),?

A lumbar cushion. Each region of the spine has a name, and the one at the bottom that should ergonomically curve “in” is the lumbar.

Give this a shot. Cheap, has the proper shape and support (which mesh doesn’t. No mesh chair can ever be good for you!), has the contoured pillows you want(need), comes in colors!