Why tcpdump shows payloads are with the maximum length of 4096 byte?

Question

I just created a sample web server and client, and I wanted to observe the packets between the two in a POST request (localhost). What I noticed while using tcpdump, is that when I send a large request body, tcpdump shows segments with length 4096 max. I'm not sure if this has something to do with tcpdump or TCP should work like this, but as I found the payload length for a TCP packet can be 65535 bytes, and I can't really understand why Is it chopped into so many little chunks. Not like It is a problem, I'm just genuinely curious and did not found any usable information about this.

Thanks in advance!