But if that happens, type 055 as the flagship, commanding premium cruiser will seem small. It might make sense for China to come up with a bigger ship as a successor to 055. A 20K ton ship could be useful as a massive carrier of large anti-ship missiles and bigger radar for fleet air defense.
During the initial developing stages, the 055 DDG was indeed designed to displace around/at least 20000 tons at full load.
However, that proved to be more than what China's military shipbuilding capability is capable of handling at the time, alongside the heavy cost, material and operational requirements which the PLAN just isn't ready to shoulder. The PLAN eventually demanded the ship designers to squeeze that full displacement down to 13000 tons, i.e. what we're seeing today with the 055 DDGs.
Of course, with the 071 LPDs, 075 LHDs, 002 CV and 003 CV being the obvious testaments, China's military shipbuilding industry can certainly build 20000-ton surface combatants for the PLAN (whether those be classified as DDGs or CGs).
However, ability is one thing; requirement is another. TBH, I don't really think that China really needs a surface combatant that large. Even Japan has decided to be realistic by scaling down their ASEV from the original plan of a Kirov-counterpart to a larger-055.
Also, what China is really looking for is the ability to field
highly-capable surface combatants
at-scale and with
bang-for-the-buck. Building just a few Kirov-size DDGs/CGs like the Soviets isn't the correct way to go for - Their respective fates are the best cautionary tales for the PLAN WRT warship procurement and sustainment.