I saw a "method" chart but it had no labels on my phone so maybe it's addressed there.
Regarding "is it paying for stuff that would have happened anyway, or is it somehow net removal?": One of the requirements for generating carbon credits is additionality, i.e. a project should only receive carbon credits if it were not viable without the revenue from those credits. But as you point out, determining additionality is rather difficult and often fuzzy.
There’s an explicit breakdown in one of the graphs, Suppliers and a graph on Price Per Method. They cover both obvious approaches to Direct air capture (DAC, Electrochemical Ocean Capture) and less obvious ones (BioChar, Biooil, Mineralization, Enhanced weathering, Biomass removal, Macroalgae).
I suspect that the inclusion of some on a reference dashboard will increase their legitimacy, and lower the case for approaches not included here. I also expect that companies will start favoring the cheapest approach.
CDR.fyi aggregates purchases, deliveries, and verifications of carbon removed and stored for more than 100 years
CDR.fyi does not track things like "avoided emissions" (like switching your fleet from gas to EV) or lower-permanence solutions (like planting trees)
(Methods show up on that chart when you hover, but good UX feedback there :)