PWA's on iOS and MacOS

Anyone with a security/developer/technical background working with iOS and MacOS willing to offer some insight into a few questions I have about PWA’s?

My questions relate to the relative strength of sandboxing between native apps and PWA’s on iOS and between different browsers (Safari vs Brave) on MacOS. I’m not looking for “what is the best?”, just an understanding of the strengths, weaknesses and trade offs between different options.

I’m aware that PWA’s are, in theory and largely in practice, sandboxed so they shouldn’t be able to communicate with each other or other sites you visit. However, I seem to have read more about security patches for Safari sandbox exploits compared to native apps on iOS. In absolute terms, the risk for either is probably low, but between the two, do native apps have some technical features that offer relatively better sandbox protections?

Now that Safari has profiles on MacOS 14, how do Safari PWA’s compare to Brave PWA’s? I know each Brave/Chromium tab/process should already be sandboxed but my understanding is that Profiles still offer better protections if there is a bug/exploit that breaks the security of the sandbox between tabs. Should I assume this will be similar with Safari? Please correct me if my understanding on any of this is wrong.

Finally, do Safari PWA’s on iOS and MacOS utilize content blockers like Adguard? I believe Brave on MacOS utilizes it’s native blocker but not an extension like ublock origin but, again, please correct me if I’m wrong.