Why can’t Kia make its cars as difficult to steal as Tesla?

I’m genuinely trying to understand why Kia/Hyundai vehicles seem to have such serious theft vulnerabilities compared with Tesla.

A friend of mine recently had his Kia Niro EV stolen from an office car park in under a minute, even though his key was nowhere near the vehicle at the time, he was out at a client meeting. That made me wonder how a modern EV can still be stolen so quickly.

Why can’t Kia implement stronger anti-theft measures similar to Tesla?

Is the main limitation cost, legacy architecture, convenience, cybersecurity design, or something else?
And for Kia Niro EV owners specifically, what security measures actually make a meaningful difference against these types of theft?