It's targeted phishing. In my country at least, it's hard to get a decent mass list of names/number pairs so the scammers rely on very dumb approaches which can be automated for lead generation, like robo dialling with recorded messages - "hello... <pause> I've been informed you have been in a car accident" and the speech recognition before putting a live agent on the call. Now with this super clean list they can do some automated profile building in advance and prepare the message - "Hello Mark... <pause> ...I've been informed you would like to have lunch with a senator". Also a lot of data brokers that provide spam lists like Lusha, LeadIQ, RocketReach will use this to enhance their databases. The profile on you they scraped from LinkedIn will now include your private phone number etc. All highly illegal in the EU but enforcement is lax and they hide offshore in the USA etc.

mobile phones tend not to be on a phonebook, and overwhelming majority of those numbers are mobile.

That is true, but I really wasn’t able to get from the article what exactly someone could do with just my name and number beyond calling me while knowing my name in an attempt to scam me.

Where I live it is quite normal to have mobile numbers in the online phone book.