Put it simple , Samsung could have offered , an sd card reader on all of it's fold line ups , the space required for that , it virtually takes no space hahah , they could have offered such on there most expensive model so say 256 go, ssd 512 ssd , OR 1t + sd card reader haha .
The headphone jack unfortunately is never coming back simple because they don't want to incorporate that .

If the S9 IS going water resistant,  I expect them to discard the SD card slot,  prehaps even go eSim .

It's a wonder you bring out advanced phone models but you take a step back but eliminating usefulness features, No SD carder reader , No headphone jack No replaceable battery haha , but people still buy the new models.  Wasn't the Samsung note 7 or 8 that had the inbuilt batteries heating up and exploding with a recall costing Samsung billions ? And they still insisted on non removable batteries,  preety simple ain't it the system just wants to stick a GPS up out backside regardless of losses lol

I knew it wont happen BUT please add 3.5mm jack to the tablet - for those of us who travel - its a must !

I still cant find a strong tablet with this jack (3.5mm)