From the AutoCAD help file:
MAXSORT (System Variable)
Sets the maximum number of items such as file names, layer names, and block names that are sorted alphabetically in dialog boxes, drop-down lists, and palettes.
Type: Integer
Saved in: Registry
Initial value: 1000
If the total number of items, also called named objects, exceeds this value, no items are sorted.
The value of MAXSORT is an integer between 0 and 32767.
Work: AutoCAD 2022.1.3, Windows 10 Pro v22H2 64-bit, Intel Core i7-8700K, 32GB RAM, Samsung 960 Pro SSD, AMD Radeon Pro WX 5100, 3 Dell Monitors (3840x2160)
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