It was pretty inevitable and entirely to be expected as the previous government waited and waited and waited before ordering new ship, the 23s couldn't be kept going any longer
They'd had their planned lives extended quite some time ago, but they're not lasting until the new planned dates. I don't know whether it's lack of maintenance, overwork, or just unreality when setting the new retirement dates.
IIRC if Type 26 hadn't been pushed into the future, T26s would be coming into service to replace the worn out T23s. We had to order the River Batch 2 OPVs, not because they were seen as essential, but because a previous government had signed a contract with BAE requiring the government to spend a minimum amount on ships each year, to try to break the expensive cycle of boom & bust procurement, which was causing delays & extra cost. A steady drumbeat of orders, keeping shipyards working, recruiting & training new workers, maintaining building yards, would, over time, save money as well as making predictable delivery of ships possible. If we didn't order ships we still had to give BAE x million pounds per year, just to maintain the building capacity.
Great idea - but despite that contract, the Conservative governments in the 2010s didn't order the planned warships, i.e. Type 26 frigates. The River B2s were ordered because they were thought to be the most useful ships that could be built quickly enough to use the money we were contractually required to spend.
Consider also the RN's AEW helicopters. The old Sea Kings were wearing out & needed replacement. A lot of money was spent examining possible replacements. Among the options suggested, but rejected, was a quick refurbishment & update of the Searchwater radars & Cerberus mission system & fitting them to Merlin helicopters which were already in service, while a long term successor was identified & procured.
Instead we had a long process of evaluation of potential successors, & selection of one. After some years, it was clear that it wasn't going well, e.g. the developer had decided to use a different radar (the original one had been a big selling point). The interim proposal resurfaced, & this time was accepted - but with a major redesign & rebuild of the radar & combat system, so we've actually got pretty much a new radar built on an old base, after a capability gap of several years, & it's probably cost more.
Politicians & the Navy seem sometimes to conspire to cock things up.