Sequential Programming is not just basic
it's also more efficient in terms of total resource consumption. For some problems, there are ways to program them in parallel, but with the use of more total CPU cycles. Which is entirely appropriate to get one's answer sooner, when the other unused parallel units would be sitting idle.
So on a shared computer, one would avoid such algorithms.
In other cases, there is no loss of efficiency; in that case, one tries to exploit the available parallelism by breaking up the program into as many pieces as can execute in parallel. Each of those pieces is... a sequential program.
But the idea of 'not teaching' sequential programming, although silly when taken literally, can still mean something that does make sense: to avoid teaching bad habits, introduce looking for potential parallelism very early in teaching programming. So just phrasing things correctly could avoid people arguing and taking sides.