I disagree and believe this should be better for founders. Demo Day works so well because it's a forcing function for getting a lot of investors to see you at once and make a decision quickly, because so many other investors are deciding at the same time. Typically, investors want a long time to consider a company, and they only move fast if someone is / might bid against them. Scheduling meetings post-Demo Day is tough, and most people do it sub-optimally (by scheduling them too far apart). This new system makes meetings happen faster and more per day, increasing a chance of getting a bite quickly, which should lead to a higher chance of closing the round.
The downside I see is that if you are bad at meeting investors / need to iterate on your pitch, these meetings won't allow you to do that, as they'll be over before you can rethink it. But I think it's generally worth more / faster meetings.
*As another investor pointed out, 20 minute meetings may also be too short. I am not sure what the optimal meeting length should be. 30 minutes might be better. 1 hour is probably too long (you can always schedule a follow up meeting).