Sure, but there are some interesting and affordable tabletop experiments being done to probe certain features of QM (like Weak Measurement: https://www.hep.ucl.

Sure, but there are some interesting and affordable tabletop experiments being done to probe certain features of QM (like Weak Measurement: https://www.hep.ucl.ac.uk/qupot/ https://www.hep.ucl.ac.uk/qupot/) and test fundamental assumptions. The work on that front is progressing, but when people think of "Laws of Nature" i.e. GR and the Standard Model, short of expensive facilities like new particle colliders or telescope arrays like LSST and Cosmological surveys, it's unlikely "new physics" is going to be jumping out of the woodwork any time soon. Which is not to say people aren't trying. Conferences are held probing this exact question (e.g. can we come up with DM detectors that aren't just enormous tanks of cooled liquids?) and trying new strategies. It's not like the community isn't engaging in good faith with some of these proposals, it's also that we haven't had a new hint of where to look from a collider experiment since the discovery of the Higgs. Despite everyone's best efforts. Yes, we need some experimental ingenuity to push through this frontier, but I also agree with OP that Physics is just being very stubborn against yielding any further secrets at present.