What capacitors are used in the Mac Studio's power supply?

Sounds like a Debbie Downer rattling off! Where did you see this report?

Electrolytic Capacitors are quite standard while there can be a small amount of deviation (tolerance) not enough to effect filtering of the EMI noise, no matter the supplier.

Now the real issue is how well your system is grounded so the extraneous EMI noise can be dissipated. Is the outlets your gear is plugged into properly wired? Is your breaker panel correctly grounded? I would get a cheap outlet checker and maybe get an electrician in to check the breaker panel and grounding system. If yours is based on a connection to a water pipe you might find the pipe outside may have been upgraded to a non-conducive poly/fiberglass one which limits the effectiveness of your homes ground, if you have grounding rods the bonding of the cable lead can breakdown and even the rod can deteriorate from age and/or corrosive soil.

As for the Mac Studio power supply it is the exact same unit the original Mac Studio had. At least from what is visible! Apple carefully insulated a good portion of the components of the supply as you can see here