It makes perfect sense from the standpoint that a healthy workforce is better than an unhealthy one. It makes sense from the standpoint that healthcare that isn't tied to your employment status allows people to take greater risks with regards to starting their own businesses, going back to school, or switching careers, which can improve the overall economy. It makes perfect sense from the standpoint that if my neighbors can get treatment for, let's say, a major global pandemic without losing their job or their house, it makes it less likely that they'll give me the disease.
Shall I go on? Love&Kindness is one argument in favor of universal healthcare, but it's not the only one, or even the most important one.
It's also, you know, cheaper. Countries with universal health care uses less money on healthcare than the US.