what if you don't know people or have strings to pull?

You start looking at industries you are interested in, then look at companies which are on an upward trajectory in those industries, look at people who recently joined those companies, find their github / blogs / emails. Start talking to them about some common ground.

You can get away without applying, yes, if your network is strong enough to get referred wherever you want to work. FAANG and similar companies absolutely will not hire software engineers without interviewing them, since the cost of a bad hire is too high.

What I have seen on occasion, especially for more senior people, is a carefully constructed charade. We're not interviewing you, that would be so uncouth, we're just having a chat!

At a bigger company, they need to more or less go through the motions even if the top person has basically made a decision after a chat and they're writing a job description for you.

At a small company, a chat over lunch that you didn't even go into thinking of it as interview may be enough.

Ask me how I know in both cases :-)