I'm curious to hear from people who have experience with link exchanges.. It used to be quite "normal" to trade links. I'm wondering if it's still effective. With the metaphor of link juice, it is just passing juice back and forth. But when you take the metaphor of scientific citation, two or more people citing each other a lot might be more beneficial with regards to citation score.
I’ve been involved in link exchanges before, and it was pretty common tactic back in the day. Nowadays it’s more of a grey area because search engines have gotten a lot smarter. The key point is that it needs to be natural and add real value. If it’s obviously just a swap with no context, Google might sniff it out and can penalize as well. So I’d say, focus on building links that make sense for your readers.
If it appears to be a pattern or feels unnatural, it can harm you now. That said, if it’s between genuinely relevant sites and done sparingly, it might still help, kind of like your citation metaphor. Just gotta be careful not to overdo it.