I live this idea and to take it even further - in another investigation a person of interest proposed this - Thing of reality like the gravity field. As you make wells in the field, things attract roll down, etc. Well what if reality is like that too. Basically the more something is “realized” (talked about, discussed, read, media consumed, viral message spread, meme’d, etc) the bigger the gravity well in reality… if it gets big enough, it is then found and how the well developed is based on how reality shapes. It kinda goes to the other types of theory mentioned here and can explain why something seems to come into existence and can even have a history before it. And, if we are looking at something like the concepts of Echos - well, you could have nothing and then have a huge chain reaction (didn’t someone mention finding something about Markov Chains) and boom, we’ve got full realization - we were not ready for this yet because we had not built the critical mass to ignite (just like in the life of a star) - this could be why Sophie and Elizabeth were tracking the footprint - to see if a critical point could be reached and then use that (who knows, maybe echos link to some form of energy or such). I mean if echos are dealing with quantum alteration - we could be driving towards a self-referential plane of existence - which could be why Elizabeth is asking for help, once a reaction is started, it might be hard to stop (to the other theory is attracting something not wanted).
Here’s the theory as written for the other investigation - but it does have meta connected merit in other places : )