Community audits sound great on paper, but it's something which the FOSS licenses (eg GPL, MIT) also provide. As a practical matter though, auditing has a two-fold objective: 1) identify risks so they can be quantified, and 2) mitigated. For non-commercial users in the community, an audit is high-effort with low return. And further, this license disincentives mitigation even if the audit does turn up something, because of having to sign the copyright away just to submit a bug fix.

For commercial users, auditing is more palatable, being part-and-parcel to risk management. And these commercial operations have the budget to do it, but then this license means the best way to keep improvements out of their nemesis's hands is to maintain an internal fork that never returns code to the public repo. So commercial users will have to pay more to obtain that sort of license.

All this seems harder than just using MIT code (or even GPL), if such is available. And that's exactly why I can't see myself using source-available software in a personal or professional capacity, when there's any other choice available. It seems worse off for everyone except the owner of the public repo. The license stinks of vendor lock-in, and even if I'm not the one who will pay the rent, I dogmatically will not support rent-seeking like this.