Please do not phone. Maybe that's not universal, but I basically don't pick up the phone if I don't recognize the caller--or at least think because of area code it may be someone I should answer. With my work number and never check messages case, I don't even have a physical phone attached to my line.
Please also do not email. It feels like every week I'm removing my corporate contact information from some obnoxious website which sells my email address having not obtained my permission to store or process it.
Presumably somewhere, long ago, there was a CEO or founder who responded positively to cold outreach from a Ukrainian outsource dev team or Indian QA company, but I find all cold outreach to be unwelcome. Making it more personal just means I have to type my "politeno" text shortcut instead of "gdprsmash".
People celebrate and mythologise the 0.1% of cold outreach success stories and ignore the fact that 99.9% of it is irritating spam.
Seems a bit like moving the goalposts. I'm saying that in the aggregate, cold outreach is annoying and unsuccessful 99.9% of the time. You're saying that's wrong because proper cold outreach "can" result in qualified opportunities (not even sales!) for 10% of prospects contacted.
In any event, your best case seems to be that 90% of people are at best unmotivated enough to ignore the message, and in all likelihood would rather it hadn't come in the first place.