We will see. Unlike Boeing, Airbus did not stretch the type beyond its three first variants, whereas the evolution from the -100 to the -10 is rather breathtaking. Yes, it adds no range variants of course, and lets see how it will fulfill EASA and possibly FAA requirements for the protection of the wet fuselage tank.
Since the development focus currently seems more on their hydrogen projects, which are all clean sheet designs, it will be interesting to see that play out. However, Airbus could obviously take another leaf out of Boeing's book and develop another new variant with a new and more efficient wing, that hasn't happened yet, they simply bolted new engines to the same unchanged aircraft with the NEO, a rather easy thing to do. But yes, there is of course a case to be made to do a larger and new plane altogether, while growing the A220 line into a -500 variant, the -300 is already competing with the A319 NEO which of course has the advantage of flightdeck and parts commonality with the rest of the series.