I used to think like you did. 

UBI is not welfare.  It is a basic income for everyone.  The amount is enough for one to survive but not good enough to have a good quality of life.  This gives people a buffer. To change jobs, to take time off, to take care of family members, to go back to school..etc.   Those that are too lazy to work, at least they have UBI instead of getting into crimes or joining hate groups to justify their existence.

With AI and automation, less jobs will be available unless they are highly skilled ones.   80% of people can't do highly skilled jobs for obvious reasons.  I suspect artisan type of jobs will be the jobs of the future. 

Trades jobs will be among the few lower end jobs that will be avaiable but there are so many trades a population need before pushing down the wage scale.

When UBI kicks in, you can rest assure than immigration policies will tighten up.   

UBI and Universal Healthcare will make things easier for everyone.  I am a ful fledge Libertarian and I support them because it will result in more freedom for everyone. 

The US Gini coefficient ranking is up there.  The only developed country in the company of under developed and developing countires. The largest economy in the world and has such a huge wealth disparity.  No wonder people are pissed in the US and want to blame immigrants, Blacks, Hispanics, China trade deficits, and all.  It is automation's efficiency that displaced these people and all the moneys flowed upwards.  

China on the other hand had to bring hundreds of millionsout of sub-Sharan African poverty level and at the moment achieved close to the US's Gini coefficient and is moving up.