There is a literal reading of the post that's correct. The deobfuscation of the above line is something like you have no visceral hands on experience with concurrency issues until you try to build a massive automated manufacturing plant in modded minecraft.
Go ahead, try and build an optimized manufacturing plant to automatically hands off manufacture all the components for something complicated like the AE2 mod, without understanding concurrency. Everything in minecraft happens in parallel, not in a single threaded machine code or abstract object model. Its like real assembly line engineering, not like writing traditional code at all. Big modded minecraft systems are chock full of LIFOs and deadlocks and queueing and latency issues to work around and debug. Minimal successful production is one thing, but perfectly optimized higher speed parallel production is a whole nother challenge.
I will admit that trying to use a single printing press to make AE2 components often annoys me enough into just building assembly lines with five presses, but that produces interesting issues of its own relating to peak to average power requirements of the entire system, and minimal latency (how do you expect something 30 blocks on a side to be as low latency as something 3 blocks on a side?)
Any idiot can make a concurrent system work by using ridiculous top tier stuff and setting the goal low enough, but its a fun engineering challenge in the true sense of engineering to make it as small, reliable, fast, and cheap as possible (plus constraints added for fun, sometimes). Both in modded minecraft and in the real world.
At this time of morning, I can't think of a kids toy that teaches concurrency design concepts better than "beyond-coursery level" modded minecraft. "Here's a cheap FPGA now implement a working pipelined ALU" isn't really a kids toy although its got similar concepts inside, and its cheap enough for a kid to afford.