Why does the Intel® DisplayPort IP TX port does not support video color depths of 12 or 16 bits per color(bpc)?

Due to timing closure issue, the Intel® DisplayPort IP core TX port does not support video color depths of 12 bits per color(bpc) and 16 bpc in the following FPGA devices and configurations:

1. Arria® V GX, Quad Symbol, HBR2
2. Arria V GX, Quad Symbol, HBR
3. Arria V GX, Dual Symbol, HBR
4. Arria V GX, Dual Symbol, RBR
5. Cyclone® V, Quad Symbol, HBR
6. Cyclone V, Dual Symbol, HBR
7. Cyclone V, Dual Symbol, RBR
8. Stratix® V, Quad Symbol, HBR2
9. Stratix V, Dual Symbol, HBR2
9. Stratix V, Dual Symbol, HBR
10. Arria V GZ, Quad Symbol, HBR2
11. Arria V GZ, Dual Symbol, HBR2
12. Arria V GZ, Dual Symbol, HBR
13. Intel® Arria 10, Quad Symbol, HBR2
14. Intel Arria 10, Dual Symbol, HBR2
15. Intel Arria 10, Dual Symbol, HBR