I'd guess that 50+% of 3rd world leaders are supported by some foreign government financially or militarily which keeps them in power.
But yes, it doesn't feel good when a foreign government tries to pick a winner in our elections.
No, I do not think those are remotely equivalent.
I totally agree that vote rigging would be particularly egregious. However, I'm not sure that backing a regime with money / weapons / training, etc. that then goes ahead and rigs the vote is that much better.
I think it's more like one scenario is stealing money and the other is investing in a gang that steals money.
I just find it interesting that we openly try to pick political winners and losers in other countries.