I've had one of These for a couple years and had no issues. Being able to roll was nice too.
Some don't have room on the desk but something as simple as a piece of mdf or plywood would help. Or something fancier like this
I've had mine on the floor for years. I put it on a riser (this one) and have done so for years. I dust out the inside twice a year.
Maybe get one of these then, to help raise your PC off the floor a little.
I used something like this
Yea, here’s the link:
HUANUO Mobile CPU Stand, Desktop Computer Tower Holder Cart with Adjustable Width and 4 Caster Wheels, Fits Most PC or Computer Cases Under Desk, Black https://www.amazon.com/dp/B07VXDSVWQ/ref=cm_sw_r_cp_api_i_zHfrFbEZ8MWMG