I have plenty of examples now where the 3-2-1 does no longer work since 2.1 dropped.
Sifi CA-D B27-3 D1 High Metal
Chromium, Zinc (C), Zirconium (E), Cadmium, Molybdenum (R), Ruthenium (VR)
Pru Eurk AA-Q D5-20 1 High Metal
Germanium, Manganese (C), Arsenic, Niobium, Tungsten (E), Technetium (VR)
Sifou XZ-P D5-1 B1 High Metal
Chromium, Germanium, Manganese (C), Cadmium, Tin (R), Polonium (VR)
Flyue Dryai IY-F D12-62 5 High Metal
Chromium, Vanadium, Zinc (C), Cadmium, Tin (R), Tellerium (VR)
Col 359 Sector IS-S D4-5 B3 High Metal
Chromium, Germanium (C), Arsenic, Niobium, Tungsten (E), Yttrium (R)
Sifou TR-G B25-0 A1 High Metal
Chromium, Germanium (C), Niobium, Sellenium (E), Cadmium (R), Ruthenium (VR)
In fact, in every case where I managed to find all 6 materials (if the limit remains at 6) then none of the surfaces strictly follows the 3-2-1 rule any longer.