RAC pensions are regulated by Revenue. PRSAs are jointly regulated by Revenue and the Pensions Authority (PA). As well as 0.05%, they charge a fixed fee per contract type (think it's €2k). The equivalent PA charge for an EPP is around €10 per annum (a tenner Vs 0.05%)
For different charging structures, a provider needs to register it as a new product type with the PA. There's an application fees then the annual fee for each type. This is why there is less flexibility on PRSA pricing compare to RACs etc. There is also a requirement for an annual return of PRSA management accounts to thr PA (income statement and balance sheet).