Keep in mind I have lived in the damp Northeast USA my whole life. Temps ranged from close to 100 F in summer to slightly below zero in winter. Have had the following cars with carbs n chokes, and made them all work reasonably well:
1965 VW Bug and 1956 VW built into Dune Buggy in the 1960s, owned it in the early 70s, had one good 1200 cc engine between them lol 1 bbl Solex choke electrically heated.
1970 Ford Torino 302 cu in (5 ltr) with Autolite 2100 2 bbl exhaust heated choke
1972 Chevrolet Impala 350 cu in (5.7 ltr) Rochester 2 bbl, intake manifold heated choke via exhaust crossover
1975 Olds Delta 88 350 cu in (5.7 ltr) Rochester 4bbl same as above
1980 Honda Civic 1335 cc, 3bbl Keihin carb, electric choke, this one never ran quite right but the choke was not the problem, it was Honda's imperfect adoption of the CVCC system to avoid cat converters that was the problem
1982 Mazda 626, 122 cu in (2 ltr) 2bbl carb, auto choke worked fine on this one.
Boat, 1988 F/W 4.3 V6 with Rochester Quadrajet, intake heated choke. It works exactly as designed, all you need to do is make sure that the thermostat is not sticking because that prevents full engine warm up and clean the choke shaft and and linkage once at the beginning of the season. After the initial start up of the season, it lights off instantly on cold starts.
If you get black smoke, your choke is not set right. Either the choke pull off is not pulling it open enough, or your float is close to flooding the engine. Black smoke is not normal choke operation and none of the cars listed above did this when I was running them. Without a proper functioning choke, after a cold start you get a rough running engine that is on the verge of stalling which is dangerous in a vehicle or boat. Stalling vehicle engine you lose your power steering and brakes, but can stil steer or stop. Boat, you lose your ability to stop completely. A mechanic who disconnects a choke because it does not work right has not fixed anything, or has failed to understand how it was designed to work and just gave up.
Example:
Ford 302 above. Bought used, realized choke was very slow to open up. Tried new thermostatic spring, same result. Did some checking, realized choke spring is heated by hot air, sucked past spring, via a vaccum port. Used a bit of motor oil in a squirt can on choke linkage. Realized that the choke linkage shaft was letting in air, that diluted the heat from the exhaust manifold. Fix was removing choke linkage and fitting fiber washers on either side of shaft as bushings to seal vacuum leak. Choke worked 100 % after that. Tried fitting a manual choke kit to it. I was the only one in the family who could get the car to start in winter with that set up! So you see, you just need to be a real mechanic.