Stop having candidates go through the full interview process if you're just going to not give them an offer because they "don't have enough experience".
It is demoralizing and inconsiderate of the candidate's time because they're probably taking time off from they're actual full-time job to attend your interview.
And please make sure your interviewers aren't on their phones while the interviewees are doing a white-boarding session... that was weird.
I thought I had a positive interview overall, and I'm referring to each phase - there were 4. Everyone was very nice and asked challenging but fair questions. But they decided on another candidate who had more experience than I did, even though I was transparent about my experience or lack there of, from the very beginning. Every phase I asked the question "Are you looking for someone who has a lot of experience in the field?" And each person said no because apparently they're all about having an environment of learning. It was an absolute bummer because (aside from their interview model) it seemed like a great company to work for, and the SRE team sounded like I could learn a lot from each of them.