To be fair they are a supremely interesting problem to hack away at, and one that will meet you where you are.

Almost anyone can put together a basic search engine in a few thousand lines of code, it's just not very hard to make a program that will index a few million documents better than Confluence.

Then, between that first ansatz and a working scalable internet search engine, you have a pile of interesting problems touching every aspect of computer science and computer hardware and networking, enough so that hundreds of people will have gotten PhDs in narrow sub-problems of those problems you'll be facing.

It's great because you can just tackle the stuff you feel comfortable approaching and leave the rest for later.