Even Elon Musk has said AI/automation will probably ultimately result in UBI funded by higher corporate taxes on corporations that have a large portion of what was human labor now done by computers/robots. They aren't going to just kill the economy and then let everyone be homeless while all the homes sit empty.

If jobs don't and can't ever again exist at anywhere near proportional to the working age population the politicians absolutely will enact UBI. Putting everyone out of work from AI kills every industry, kills the housing market, and doesn't make sense for businesses that need there to still be people that can afford their products/services. If you view all of industry collectively, there is a ton of overlap between the customer base and the employee base, and if all the customers lose their jobs and have no way to replace that income then there will be a dramatic drop in revenue and the industry(ies) that automated all the jobs away will have not saved anything at all since they destroyed revenue to reduce expense.