public reviews in conferences [D]

Why don't all conferences make reviews public?

I find ICLR public reviews to be very useful :

- I get an idea of how others in the field think about the work

- Makes the publishing process more transparent

- Reviewers will potentially spend more effort to avoid public scrutiny

Are there any drawbacks in having ICLR-like public reviews? (where the reviewer identifies are masked) Would the community benefit if all conferences released their reviews?