Classic car as a daily runner?

I used to run classic cars all the time, mainly because it was all I could afford to buy more than anything.

What with the rising costs of car tax, fuel, and maintenance which isn’t owner friendly anymore I got to considering whether it is worth reverting to a pre 1973 classic car again as a daily runner.
Tax is free, they are comparatively easy to maintain at home, and I never found them that much more expensive in fuel consumption to a comparable capacity modern engine.
The missus has a modern small diesel as a car that we can rely on for long trips etc.

It is only hypothetical really (though an old Landy Srs2A with 200 tdi would be nice), but what’s the thoughts here about this, on practicality, types of cars etc?