I know what it’s like to have people who you respect turn out to be MAGA. You spend a lot of time trying to come up with an excuse so that you can reconcile your respect for them with the horrible shit they are staunchly defending. And what you say is definitely true, or at least was. But Trump was initially elected in 2016. He has been on and in the news daily for almost a decade.
People who are still MAGA, have made a choice. They have either decided that they are ok with it all, or they are willing to pretend and look away. They choose the echo chamber to drown out the reality that they want to ignore.

Considering that Elon was an illegal immigrant to the US at one point, I question the legality of his citizenship.

As some others have pointed out, paying social security directly costs companies money.
However, there is also a secondary set of costs to social security. Social security dramatically decreases a companies grip on a worker as the worker grows closer to retirement. A lot of workers would not be able to retire with out the income that social security provides. Without social security, once a worker passes the age at which they become less desirable for other companies to hire away then they essentially become slaves. And knowing you’re heading towards what is essentially slavery is going to have a lot of knock-on effects too. Pay and compensation negotiations, changing companies, how afraid people will be of being fired, ect… Are all going to swing heavily into the companies favor.