That's why for every very high value use case (see chii sibling post) you keep some low value use cases running that don't really require high energy concentration fuel. Burn shrubs, waste (e.g. bioplastics), whatever for heat and stationary power and capture that CO2. Low concentration fuels are well available in renewable form and will be forever. Bottleneck solved, at least as long as you don't imagine you could keep up fossil age consumption rates with synthfuels (you can't). Leave those many millions of tons of air to processes we already run on them anyways.
You are right (also with that last paragraph), direct air capture is usually a scam. I might be willing to grant a weak exception to projects that put serial self-containedness front and center, e.g. terraform industries (not to be confused with terraform labs...) would certainly be overwhelmed if they tried to tailor a capturing biomass plant to the local situation with each installation. But even they should better spell out in their advertising "optional, could be substituted with:" for the DAC.
You are right (also with that last paragraph), direct air capture is usually a scam. I might be willing to grant a weak exception to projects that put serial self-containedness front and center, e.g. terraform industries (not to be confused with terraform labs...) would certainly be overwhelmed if they tried to tailor a capturing biomass plant to the local situation with each installation. But even they should better spell out in their advertising "optional, could be substituted with:" for the DAC.