Yeah, I agree. Literally even budget phones have this feature and on A series we cant even use a 3rd party app to have actual shutter speed (it exists but only up to ½ to 1 seconds). The a series should support it and if they are being marketed as phones with amazing cameras. They have the hardware for it clearly (The newly released Galaxy A71 and A51 have great quad camera hardware, a 64mp f1.8 lens for the A71 and 48mp f2.0 for the A51, and with the inclusion of the Snapdragon 730 the A71 is probably the best midrange phone). All A series phone from 2018 onwards should get this shutter speed option (including A8 2018 Samsung, stop treating it like a 2017 phone not even getting android 10)
I asked through Samsung members and they said that they will give the feature as a suggestion but they won't probably add it because it would raise the cost of the device and they want the a series to be affordable to everyone. However if the feature already exists (on every other phone and the S series and Note series), then how would it cost them to add it? It's like saying that pre-installing the free Samsung calendar app will make the phone more expensive, even if it already exists and they don't need to develop it.