It's basically the same as any other rule: if everyone follows the rule, you get a better result than when the thing is voluntary.

Imagine there are no taxes and no welfare programs. Spending resources on the welfare of others is entirely voluntary.

Let's say 20% of the population does this. What happens? The 20% of the population which is the most altruistic has fewer resources, some of which was given to the 80% least altruistic people.

If you do this repeatedly, what happens? The least altruistic people end up with the vast majority of resources. This is bad.

What do we do instead? We establish a governmental welfare program, and we make everyone contribute to it, regardless of whether they're altruistic or not.

The government already takes our money. We want our money to be used to benefit working-class people, not used to build child rape islands, bomb half the globe, and carry out industrial-scale holocausts in our name.

It's not even about "spending your own resources on others". Its about where the government spends YOUR money.

If I pay $100 dollars in income tax (for example), is the government spending that $100 dollars on MY healthcare, MY roads, MY sewage and water lines, MY roads.

Or is the government handing my $100 dollars off to private contracts who are then profit motivated to spend only $20 dollars providing those services so that they can keep as much of it as possible?

Socialism isn't "free stuff" or directly paying for other peoples stuff. It's about making sure the tax dollars are spent on US. When that happens, a surplus results that allows us to help others who are struggling.

Because you and the person in the post have the same misconception of what socialism is.

Welfare state =/= socialism.

Because the government won't let you die. Say that person that said "I'm opting out" loses their job and maybe gets a chronic sickness. Now they have no disability, no food stamps, no medical. They're literally dead if they don't have someone they know willing to support them.

Say one family member works and the other is a stay at home spouce and they have 2 kids. Same thing happens, except they're all fucked. Can't use the resources because "you opted out of that stupid shit".

Everyone wants to not pay into it until they need it. I'm not saying it's handled the best, not it keeps people from dying.

Economy of scale.