The Netherlands, much like the British, have reduced their number of ASW frigates and are increasing their number of sealift assets. The Cold War is over, the peace dividend has been cashed, and now nations are rebuilding their forces to match today's problems, for many its sealift.
Since no European or American navy has over 100 submarines anymore, ASW has taken a back seat to sealift. Sealift and littorial warfare assets are the wave of the future, with frigates being useful abroad on peacekeeping missions and with OPVs being useful at home for EEZ patrol, fishery protection, SAR missions, and for showing the flag in foreign ports. OPVs also cost much less than a frigate, several times less.
Even a more powerful corvette of the same size of a OPV have the combat data systems and weapons systems of a frigate are half the price of a sea going more heavily armed frigate. Welcome to the 21st Century
Here is a link to the Armada magazine article which shows two pictures of HDW AOR/Sealift multi-role vessels offered to Portugal. The 8,000 tonner appears much like a small LPD, the 10,000 tonner appears more like a midships flat top, with the repenishment rigs to starboard on both.
www.armada.ch/05-5/complete_05-5.pdf