That style of funerary artwork in Egypt is from the period when Egypt was part of the empire, and the very few surviving scraps of Roman paintings suggest that the style was widespread, but has only been preserved in any significant quantity in Egyptian tombs.

The big issue was that the paints they had to work with at the time were expensive and shitty, being difficult to work with and extremely delicate once placed. Hence why most surviving artwork are janky, mass produced murals where the color was protected in the tile, crude graffiti that got protected from the elements, really anything where the color was fixed into a more durable form, and things made of stone or metal which lost any enamel or paint they may have once had.

But there were definitely still skilled artists all over the place, both in the form of realistic painters, in sculptors, and in more stylized forms like pottery (like that weird stylized figure style that gets associated with the Greeks was basically just a technical method of getting clear and durable figures onto pottery) or mural creation. It's just only a tiny fraction of the work from that time has survived to the modern day, and the vast, vast bulk of artwork produced in that era was cheaply made template work designed to be mass produced so that's what we most associate with Classical art.