Simplest answer: it enables programmers on any variation of an OS to get code. If I’ve got a python requirements.txt, getting those requirements installed is the same on any system I’ve got an appropriate python version. The designers of the languages effectively deemed that an important goal and explicitly put in the effort to include package management, in at least most of your listed cases.
My ISP charges a good chunk for static IP (because they consider it a business connection). However, my $10/mo VPS (which I already had for other projects) has its own static IP and I can easily proxy individual requests through it as needed. Have looked at VPS instances for $5/months before.
Depending on the service, your ISP, and how easily you can change IPs in the registration, as others have mentioned, you could just give them your public. I’ll say my own public does change at least twice a month, so if I can’t automate updating a registration, it goes through VPS or it’s a service I just skip.
S&P500 lifetime inflation-adjusted return is 7-8%. meaning, if one put away 150K in the S&P500 at age 20 and worked for 40 years, putting away nothing else but gaining that inflation-adjusted 7-8 (conservatively call it 7), and then pulled out a measly 4%, allowing the remaining growth to account for inflation, they’d be pulling an inflation-adjusted income of >80K, ignoring any other income.
I’m not saying one shouldn’t put anything else away or strictly count on matching historical S&P return, but yes, putting away 150K at 20 could absolutely mean you don’t need to put anything away again.