I don't believe that LSPCON is still used in Alder Lake+ designs.
The display block in older Intel GPUs (Gemini Lake, Tiger Lake) could provide only one HDMI 2.0 port natively. Some of those NUC designs had two HDMI 2.0 ports, so they had to use a DP-to-HDMI converter. Some devices had one native port + one port via DP LSPCON.