I agree. However, there have been many times where a company will set up a psp with the full intention of funding it. Then for some reason or another, the company is unable to fund their plan. At which point, you would have eligible participants, but no assets.
In this case, I believe a 5500 should still be filed, hollow as it may be.
Reasoning: You have a written plan, the plan has been submitted to IRS for favorable determination, plan has received favorable determination, plan has received a trust ID number. For all intents and purposes, a plan exists. Isn't it a requirement for all plans to file a 5500?