I agree with you that in an ideal world there'd be a way for you to demonstrate your prowess without playing these games. However, in the real world, I want a job, I'm going to play? It's not like I don't solve hard engineering puzzles for fun on my own time anyways. Framing matters a lot!

Here's what I like about interviews:

(1) I get to talk about myself and how great I am without people rolling their eyes at me.

(2) I get to solve a fun puzzle with:

(2)(a) A defined answer.

(2)(b) That I never have to maintain.

(2)(c) With a potential financial windfall at the end.

Seriously though, in Europe the Algorithmic style interview is not the norm, by and large

Interesting, what's the process there like?

Plain old style interview, you get through HR, get a couple of interview rounds with people from different departments, discuss with them several subjects somehow related to work, positive and negative experiences across your career, what would you do if X happens,....

If you happen to do coding exercises at all, they are just basic tasks like implement a linked list data structure, count the number of words on a file and such.

Answer some trivia about the language you are supposed to use, e.g. when should you use a struct in C#.

Luckly only startups over here are somehow into SV hiring culture, which still leaves plenty of others with job offers available.