Does PLAN really need several dozens of 055? PLAN doesn't have many oversea bases or former colonies to assert influence, say in the case of France or Britain; nor does it have to be the GLA. Those are expensive large warships, often overlapping in roles that could easily be covered by long range land based missiles and jets.
China has invested heavily in the Middle East and Africa, and those investments will only increase over time.
Along with said investments have also come significant Chinese expat migration.
Just look at the costs China suffered in Iraq and Libya following Western backed regime changes and the mass evacuation of Chinese nationals Beijing had to organise.
In future, such losses will be far higher and evacuations more difficult.
Contrast that with Syria and Russian involvement.
Having a powerful blue water fleet would allow China an effective veto on western back regime change in nations China have significant investment and stakes in. That in turn should act as a deterrent against military misadventures by other powers.
A good example would be the PLAN deployment on a 052D to waters around the Maldives, which is argued went a long way to deterring overt Indian military intervention.
That’s not something you can do with missiles or land based aircraft.
Case in point is Venezuela. Did Russian Tu160s landing there dissuade American regime change efforts?
Things might be different if Russia still had a powerful blue water navy they could send in, but they don’t, so civil war and/or regime change looks to be a matter of ‘when’ and not ‘if’.