The circuit does work great for a pumpkin lantern but his video is more of a tutorial on coding linear congruential generator (LCG) for the 8 bit pseudo-random LED flickering. The code is short ...

[KK99] has created the simplest possible pseudo-random binary sequence generator, using a three-bit shift register. ... but the point of this circuit is to educate rather than its utility.

Assigning “1” for heads and “0” for tails, we generate a random sequence of binary digits or bits. Ten tosses might produce a sequence such as 1001110100.

Thus, the sequence has limited length, and the generator continuously repeats the same pattern. The generator in Figure 1 overcomes these limitations by using random noise to form the outgoing data ...