That takes less than 10 seconds to say, let's you protect your time and peace of mind, and as a bonus there's no need for fuming, blaming, and judging that the other person won't ever even know about.
No, that obviously false. They might be more likely, but they are certainly not likely.
Not even close.
This is 100% completely on you, then. If you don't inform people you're being interrupted or that what they are doing is bothering you, they have no data to telling them to stop, and any energy you spend on silently judging them or being frustrated is only harming yourself.