I do agree though that some of our frontend interviews are a bit heavier on code + css and less on systems design thinking.
Btw just to clarify, we have a policy where we won't host any interviews that are just open dev tickets to build a feature that will be used in production. Like, we DO NOT tolerate companies using interviews to get free labor.
What does that change from a candidate perspective? In both cases the candidate wastes their time. I'd offer a better solution: the company pays market rate for the time needed for the test, and can then ask for anything they want - in which case an actual ticket is the best solution as it will evaluate the candidate's performance on the kinds of problems they'd actually be working day-to-day.