My experience with the many of them I have owned over the decades is that seldom are they designed for actual effective dust collection.
One of the very best 16" bandsaws I have owned was a 1930's style Davis & Wells that was built circa 1950 and was still new in a crate when I bought it in 1959. Of course the dealer replaced the blade tires and the belt. The bearings and guides accomplished just about everything as on a 2012 bandsaw, except that D&W had no provision for dust collection. The nature of bandsawing is that the narrow blade does not create the volume of dust, relatively coarse dust, as do other woodworking tools. Right after a session sawing I would use a shop vac with a long tapered nozzle to clean all those places below the table where dust would cake.
In 1960 I opened a precision machine shop, for which I bought Do-All metal cutting bandsaws. They had blade welders, but no kind of dust collection ports.
For my current cabinet shop I own 2 Agazzani conventional bandsaws, which have about as good dust collection as I have found on any woodworking bandsaws. The thing is having the high velocity of a Festool CT is not going to help. Bandsaws with dust collection need the low velocity very high volume of traditional plant DC systems. I have seen demonstrations of 20" Agazzani doing re-sawing at trade shows where a 1.5 hp portable DC was keeping pace, using a 100mm hose. Both of mine have 150mm hose connecting them to my plant DC. Still when we finish with a bandsaw operation, or at the end of a shift, we use a CT22 with cleaning nozzles to remove residual dust under the tables.
My other bandsaw is a lumber mill-style Baker horizontal. By the time we receive rough lumber it has been carefully dried. In use it creates a lot of dust and chips, probably more than our CNC nested routers. It has three areas with 150mm DC connections and we use all of those.