If you are connected to 125 nodes, then for 200 TPS only the hashes already are 0.8 MBps:
Why would you need to be connected to that many
full nodes? I don't see the need for so many connections. And SPV nodes only care about the transactions that concern them, which are always a very small set compared to the total that passes by on the network.
At maximum hashes would only need to be 16 8 byte first bits, likely even less.
125 * 8 * 200 = 200000 = 0.2 MBps
Aren't you mixing bytes and bits there? Bps normally means bits per second, not bytes. And 8 bits only for the hashes seems too low. You only get 256 different values, with 200tps you'd have lots of collisions. 8 bytes on the other hand is even more than the poster you replied to was talking about (he mentioned 32 bits, so 4 bytes).