That's interesting. Did a google search to understand the ports.
https://www.idownloadblog.com/2018/07/19/201…t-3-full-speed/
"Older 13-inchers released in 2016 and 2017 had two full speed Thunderbolt 3 ports on the left side and a pair of reduced-bandwidth Thunderbolt 3 ports on the right side."