system
Given the following post, respond as if you're commenting on Reddit:
human
[Assassin's Creed II] Why did Subject 16 "encrypt" his massive secret with a series of simple puzzle games that basically anyone can do?

I loved Assassin's Creed II when I first played it primarily because of the mystique of the puzzles and the crazy ending. I'm replaying it now and I can take or leave most of the game, but I almost was playing it just for the puzzles eventually.

The only thing is that now that I'm older and more experienced with puzzles, math, and logic in a fairly amateur way, they're MUCH easier than I remember. It takes a long time for them to even get remotely difficult, and even the hardest ones are pretty straightforward. You can use partial guessing to simplify ones you don't know like the art puzzles to a few solid guesses and brute force the rest in seconds. The ones I enjoyed the most were the number wheel ones, but they were pretty easy too. You could take for granted that if you could line up two of the relevant numbers with blank spaces, that was likely the correct alignment. It's basic math from there.

Overall, the Subject 16 puzzles are fun for the mystique, but what was the point of using them to encrypt a secret about all humanity? They're not that hard.
gpt
The encrpytion wasn't the main protection.

Remember Desmond had get the secret by scanning each glyph with eagle vision. To do that he had to relive the most important part of Ezio's life through the Animus. A process that imbued him with the skills Ezio learned and taught him the history and philosophy of the Order. In other words, a process that turned him into an Assassin.   

Clay *wanted* his secret to be found and hid it in the Animus in such a way that the finder would become an Assassin who could then be trusted with the information and be able to escape to spread the word to the Order.