I have been looking at BLE with the Nordic products from the perspective of someone who gets a hand wave of an idea and moves forward. I have developed Nordic firmware but not actually "learned the SDK" to any major degree past what I needed to get ESB or Matter to operate.
From my perspective in using the old SDK, Bluetooth required integration of binary blobs called Softdevices. These had code numbers like S110 or S140.
With the newer code using Zephyr, there now the opportunity of compiling Zephyr sources Bluetooth control (called the LE Controller under the Zephyr docs).
There is still mention of the Softdevice, but now it's a library that you compile inside of zephyr.
Are the old softdevice names of S140 and such no longer used then? Is the Softdevice used with Zephyr projects recompiled to operate with Zephyr?