Why is Poisson process, a very special process

Queueing theory is an area where one can find superb applications of various stochastic processes. Here is an adapted visual from Kleinrock that gives a 10,000 ft. view of the various processes. The visual below, at once, explains the reason for Poisson process being so special. It is a process that is an intersection of Semi Markov process, Markov process, Random Walk process, Renewal process and Pure Birth process.

It is in the sweet spot, so to speak, of six popular stochastic processes.