I was an aide for several years before and during nursing school
Being a CNA is practicing the art of basic nursing care. That is taught in nursing school, sure, but it isn't practiced very much during clinical. People that work as a CNA on the other hand, may have had years of practice with basic patient care while working before they ever even set foot in a clinical setting. It helps immensely during school since you won't need to spend very much time mastering basic nursing skills - personally it made my first semester a breeze.
It would help you understand that healthcare isn't some glamorous job like they show on TV, where everyone is hanging around the nurse station saying witty one-liners or there's some kind of drama happening.
Also, becoming a CNA would be the first step to assuming your identity as an RN. I know when I started working as a CNA I was really proud of it. Like, I provide healthcare, this is what I do. Now many years later I can look back on my resume and I'm proud to say that except for a short gap when I tried to switch fields and be an electrician, nursing care is what I've always done in one form or another.
I remember I had a classmate drop out of RN clinicals after a month and a half when she was exposed to the reality of nursing care. She didn't like it. She decided to be a respiratory therapist instead. But if she had been a CNA she would have had an idea of what she was getting herself into. In that sense, being a CNA is a good way to test the waters and see if nursing is a good fit for you. I remember being 19, in a CNA program, and setting foot for the first time in a clinical setting. I walked in and said hi to the patient I was assigned to, he mumbled something and pointed at his butt, I looked under the covers and there was poop EVERYWHERE. That was my first lesson in assisting someone that was dependent on me for their care. Its never really got any better but at least I knew what to expect after that.
I also got to work in several different areas as a CNA- something that I'd never get to do as an RN without extensive orientation. It helped me figure out which area was a right fit for me and I was able to pick a job I liked right after graduating - some RNs graduate, take a job, hate it, then switch areas within the first 6 months and then bounce around until they find one they like.
Does it help your time management? Yes. It helps you learn how your day should be structured into manageable parts to get the tasks done that need to be done. Show me a new nurse that skips breaks or stays 3 hours after their shift charting and I'll show you a nurse that probably never worked as a CNA. Being a CNA taught me how to get done the things that needed to be done in a certain timeframe (generally revolving around when it was time to eat).
Does it help you learn the tricks and techniques you need to provide care? Yes. I'll use an example, putting a plastic bag over someone's foot while getting their TED hose on makes the process as easy as putting on any pair of socks. They didn't teach that in school, I learned that on the job as a CNA. I make sure every single one of my patients gets a bath everyday, even if I have to do it myself...something I learned as a CNA. Some of my RN coworkers don't even pay attention to whether their patients get bathed or not. If there's an RN reading this, when is the last time you asked your patient the last time they got bathed? When is the last time you made sure your patients belongings were in reach when you left the room so the patient wouldn't hit the call light 50 million times for this or that? When is the last time you got up and rounded on all your patients to make sure their needs are met before you went on break so you don't get interrupted? There's many many other examples I could cite that I simply learned or got in the habit of during my experience as a CNA.
I don't know any nurses that think they are above CNA work, however I do know a lot of CNAs that think RNs are lazy or purposely avoid answering call lights etc etc. I think there is a huge misperception and blurring by CNAs over what exactly the RNs role is in the clinical setting - I know I used to carry that same misperception. However, having been a CNA before being an RN, I can see both sides of the coin and I understand where they're coming from.