People stick with service providers for a long time. The lead that the landscaper in your example is building now actually compounds over time, regardless of whether competitors adopt grok bot in the future or not?
In your 2008 example, making a profit was contingent on cashing out (selling your property). Whereas the landscaper is expanding their book of business and increasing their future cash flows.
Unless you think there will suddenly be some sort of rug-pull in his ability to use AI tools to manage his comms, or a sudden change in long-standing consumer behavior around landscaping services... I don't understand how you can in good faith think these economic scenarios are similarly risky? What debt/leverage is the landscaper taking on by using grokbot?