Is the porpoising caused by regulations? I've understood it as teams not wanting to make alterations to prevent loss of aero, but they are able to fix it if they wanted to (like other teams).
The regs are definitely a part of it with the restrictor plate. Theoretically the regulations could dial back the porpoising by making changes to suspension and aero design, as well as altering the specifications of the tyres. At the same time, teams also have some responsibility to the extent the Technical Regulations allow engineering to make changes to the car.
2026 regs will reduce overall downforce and simplify floor design so the cars will be less reliant on ground effect. I'm not an aero engineer, but I suspect porpoising will be less of an issue because of this.
I am an aero engineer, but primarily with a focus on spacecraft design. I can do a deep dive on the regs and maybe see what I get from them, then potentially do a series of posts, assuming the community would want that.