My WD Elements 4 T HD isn’t seen on either of my smart tv’s via there USB ports. It’s seen by my laptop. My WD 2 T Passports work fine for seeing video on my tv’s.
You need to check 3 things about your TV and/or compare the 3 things below with your working 2TB and your non-working 4TB.
What is the Maximum Capacity your TV Supports ? (2TB,4TB,8TB etc)
What File System Format does your TV Support ? (NTFS, FAT32, exFAT etc)
What Partition Table does your TV Support ? (MBR or GPT)