Good catch — DPR/display scaling isn't a first-class axis in what we record today.
Right now, Record captures the in-game screen size/resolution, and Replay tests different pixel resolutions by driving the RenderTexture directly (1280x800, 1920x1080, 1920x1200, 3440x1440, etc.).
What we don't currently capture or replay is Windows display scaling (125%/150%) or a DPR-equivalent value as part of the environment. So while we can compare behavior across different pixel resolutions, a same-resolution/different-scale issue is a real gap today, as you said.
I like your framing of Resolution and Display Scale as two separate test axes rather than grouping everything under "DPI issues." A matrix like 1920x1080 @ 100% / 125% / 150% makes sense as an orthogonal dimension on top of the resolution testing we already do.
Since GameCheck is Unity/native-first, the mechanics are different from the browser case you described, but the core point absolutely carries over: resolution and scale can produce different classes of failures and should probably be tested separately.
Adding this to the roadmap as a gap worth solving, not just a nice-to-have. Appreciate the detailed breakdown — genuinely useful way to think about it.