I wonder how well your average computer motherboard would handle being in a pressurized air environment. Like your sea level pressure is like 14 PSI, and inside a car tire is like 30 PSI. I wonder if any components would fail at the latter pressure?
The problem there was that helium diffuses through everything extremely easily. If you had a diffusion-related problem with air at e.g. 2x higher pressure, it would simply manifest ~2x more slowly at normal pressure.