Somewhat disagree, depending on the embedded subset. Lots of MCUs don't have any cache, so they don't have any cache lines. If you're programming some sort of embedded Linux system you'll have a more powerful processor and almost certainly have cache.

So if you're hiring for MCU work (bare metal or RTOS) the concept of a cache line isn't important. If you're hiring for application processor work (often Linux), it's very important.