Please note at the moment that the Allies in the Mediterranean are currently supporting ~25 divisions in contact with Germans. There are broader and deeper logistical flows and a bit less demand on amphibious shipping at this time compared to OTL but the gains are only so much. Also note that the US is beginning to make large multi-division assaults with huge jumps from major bases in the Pacific so US amphibious shipping demands in November 1943 TTL approximate US amphibious shipping demand in the Pacific OTL July 1944.The fleet that landed in Anzio is shall we say free TTL?
LSTs are still a very rare and highly valuable commodity.