This feature was returned, to a degree, in Android 6.0+ with the introduction of adoptable storage.
To put it in perspective though, there are many reasons why you wouldn't want your apps on your SD card. For one thing, SD cards are generally much, much slower than the internal storage of your device, and is especially true of more recent flagships. In some cases, this may cause certain performance issues with some apps.
In either case, you can still use your SD card as general storage for photos, music, movies, etc. This frees up that space on your internal storage. The end result is still going to be extra space for your apps.