I have a Mac Studio M1 and a Macbook Studio M2. Thus far, Houdini has been flawless. That is, until I used heightmaps in COPS. I understand that the Mac's GPU capabilities aren't as high as many GPU's on a PC. But this seems beyond bad. I'm just wondering if I should bother with heightmaps at all on Mac. Even very basic displacement is like <1fps update.

Any suggestions (besides the Buy a PC suggestion?). Maybe I'll have do this kind of work in substance designer until its better?

SideFX, is there anything hopeful coming in the future to improve this?
Thanks in advance.

which version of Houdini are you using? I did report a very bad lag in the viewport when upgrading to 20.5 so I rolled back to 20.0.7
where the problem did not exist. And I use a high end PC.

(the popular issue of the 13900k / 14900k and Bios settings was blamed. I do not agree with this!)

try refreshing the viewport.
try smaller height maps.

I found that just adding a null after the height map helped but would lag after loading in each day.
I ended up rolling back to 20.0.7 as I like to zoom in and out and spin the viewport to see what is happening and 20.5 was just so frustrating I could not use it.