The comments above you replied to were saying something different to your interpretation, I believe.

They were saying that by going remote (the last 5 years), people haven't formed as many deep connections by legitimate social connections at jobs and their reputation. You could say this is the "good" or "reputation" based way of getting jobs in the back door and it's not all just likeability. So there is less of this kind of back door hiring right. I don't know if this is true or not.

But the back door hiring for nepotism or "my brothers girlfriend" is still as ever present, since the connections aren't predicated on real life in person social interactions.

Discrimination or disadvantage comes in to neither of these hiring methods innately. Subconscious bias could exist for back door recommendations ofcourse.

So if anything, it's not really leveling anything. It just means for increasingly experienced engineers, benefits don't accrue so much when looking for work if remote. If anything these backdoor references could help people (e.g. from poor families) get a shot even despite other innate culture differences (e.g. style of speaking). And nepotistic hires will remain.

Think it has to do with trust. If a hiring manager, for example, has a contributor who is good and recommends a former colleague, that resume can get to the front of the line. There are plenty of engineers who are interview/leet code ninja's or have fluffy resumes. Getting someone to vouch for work ethic, skills, etc of a candidate carries allot of weight. Thats just the reality. Its less risk of a bad hire if you have first hand knowledge of a candidate.