Let me tell you a bit about my life. My mother has the amazing quality of picking a new hobby every year to get invested in. She spends thousands of dollars to get all the gizmos for her newfound passion and two weeks in, she loses interest. She's done painting, knitting, yoga, macha tea, whatever some lifestyle blogger tells their audience has solved all their problems, she bites her teeth into. The result is that the entire house is filled with unfinished projects and garbage to the point where doing laundry needs an appointment like a doctors visit so she can make the washing machine accessible. She finally settled on gardening, which gave me the false impression that the excessive hoarding would come to an end only to find out that apperantly 100s of flowers have to stay inside the house during winter. And despite it being her personal hobby, it has to be everyone's problem.

At some point I've had enough. I've made it very clear that when she finally meats her end that all of this, all her legacy, goes straight to the landfill. I have exactly zero sentimental or positive memories associated with all that garbage, and I will not lift a single finger to preserve it. The only memories I will have are all the times I've almost broken my ankle trying to step over carboard boxes. I asked her flat out if this is what she wants me to remember her by?

Now this hasn't solved the problem, but at least it has put a lid on it. I guess when you are faced with your own mortality and what you'll leave behind, it makes you at least think twice about your actions. Now as harsh as it sounds, my mother is in her 50s and in somewhat devent health so death isn't exactly waiting around the corner for her. Your dad on the other hand... I'm knocking on wood here, but in your situation this approach might be more effective.

Just ask him what he wants to be remembered by? All the good times you had, or how he spend his days watching AI garbage and whining about your own interests?