I've never been a research assistant before. Can anyone offer me what it would look like or what it translates to on a CV?

For context I did my undergrad in biomedical engineering and have been working at Merck in a robotics startup. I'm 27, I really want to go to vet school. I'm getting a masters to strengthen my application.

I recently was offered a research assistant position in vascular biology. The PI is the director of vascular biology and his post docs say he's fantastic as a mentor.

I'd be leaving a good paying job for something really low paying all in hopes of strengthening my background in science and hoping it looks good for vet school applications.

Is that a bad decision? Would I learn anything in this job? I'm getting misinformation from people who work in academic about how much this job is useless and I'm worried now.