One thing I would do a lot with Google Scholar is find a highly-cited, somewhat recent (past decade or so) paper and then click into its citations to find the very most recent related work. IIRC this interface was chronological so there was no big-journal bias and I found a lot of stuff in random journals. Low-friction quality-filtering through SciHub was very helpful for me in this process.
I worked in a theoretical field, so it's actually possible to assess the quality of a paper just by reading it. If you're doing something experimental you may have to lean on the big-journal filter a little bit more.
Under what conditions do you see that changing? You yourself say how useful it is, but discount the effect it has on the citation graph. Could we say the samething about arxiv?
This is exactly why research needs to be open and freely available. The esoteric, rarely cited papers are locked behind paywalls and away from search engines. And in doing so, their impact fades over time as the flock centers around a single vein of focus. The future should look like a net not a river.
I am not an academic and I read papers for their metalessons in areas that interest me. But without Sci-Hub, lots of research would not be accessible outside of its niche, esp if it was unlucky enough to not be in the right journal at the right time.
On hilarious pattern I see, is when a bigshot in a field publishes a new paper, there is a race to cite it by some nobody. Basically the academic publishing version of "first post".
As to why my lab might be preferring papers from big-name journal: I think 1) there's admittedly our own bias of wanting to cite big papers vs. small papers, 2) if we're doing some basic literature search, Google will also yield results that are already more popular. Really, at the moment, I struggle to see how our behavior changes about which papers we're citing with or without scihub.