@whyrichard
Unless somebody has spilled congealed porridge or an equivalent on your records, I think you are mainly dealing with dust attracted by electrostatic forces to the vinyl.
Any time you rub vinyl with an insulated material, electrons are displaced. The insulated material can be cat fur, velvet, paper or even in my opinion the diamond stylus.
According to Wilson Benesch, details down to one micron can be retrieved from the groove. That’s a thousandth of a millimeter. No brush can get that deep.
Electrostatic forces are incredibly powerful and like gravity obey an inverse square law in distance. At one micron, the force is a million times stronger than at one millimeter. The best way to unstick the dust is to discharge the electrons and wetting with water is a great way to do that - see Anton’s excellent book entitled Precision Aqueous Cleaning of Vinyl Records available free here: PACVR-3rd-Edition.
I believe that once the electrons have been freed, the best way to release the microscopic dust is with a no-contact ultrasonic cleaner. I use a relatively cheap Chinese one before I play new records, as well as on all used records. The secondhand records I buy in general are as click-free as new records, but they are mostly classical and have probably been well looked after by previous owners.
I do use micro-line stylii which tend to read parts of the groove that have not been worn by conical, elliptical or Shibata stylii.
I follow Anton’s advice and use deionised water plus wetting (Polysorbate 20) and drying (Ilfoton) agents, and air dry the cleaned records vertically in a rack which came with the ultrasonic cleaner. No rubbing! I replace the inner sleeves with anti-static ones from Nagaoka and use an AudioQuest conducting carbon-fibre brush recommended by TAS.
A while ago I was ridiculed for pointing out how much stronger electrostatic forces are than gravity. Electromagnetic forces are hugely bigger than gravitational forces – about 36 orders of magnitude greater. While you can flick away surface dust (gravity deposited) with a feather duster, electromagnetically bound dust sticks very firmly