I started applying for sponsorship 2 years ago and had no flying experience at that time. I managed to get through the first couple of stages with no flight experience, so it man not be that important.
I now have my ppl, which I got because I love to fly. I hope to progress through to atpl standard if my sponsorship applications prove unsuccessful.
I am getting through the various stages of sponsorship programmes just now and that is with flight experience. My experience shows that you don't need flight experience to apply for sponsorship.
If you are going to learn to fly, I suggest you do it for fun and not in the hope that it will help you through selection.
All the best,
Russell.