Is there something special about the software in new Boeings? Dual engine failure is nothing to sneeze at, and should never happen. Airbus also had its fair share of software errors in history, but if we count the recent Lion air crash as software related, Boeing has had 2 serious software related incidents in a year and I haven't heard anything serious from airbus.
Is it because Airbus started its fly-by-wire development earlier?
I think with these types of incidents being very rare, it's hard to extrapolate to any kind of patterns.
Not within the year, and I'm sure there are more (for both Boeing and Airbus), but this one comes to mind on an Airbus that's pretty scary -- thankfully occurred at cruising altitude: https://en.wikipedia.org/wiki/Qantas_Flight_72
It's not the aircraft, it's the engine. Boeing 787s have been grounded recently because problems with Trent 1000-C have been increasing. Mainly compressor blade durability.
Modern jet engines like Trent 1000 from Rolls-Royce have
Full Authority Digital Engine Control (FADEC). It comes with the engine and there are no manual overrides. The computer system runs the engines and if it fails the engine fails almost instantly.
Before the flight pilot sets flight parameters to flight management system (FMS) and FMS communicates them to FADEC in the engines. FADEC runs the engines and 'micromanages' the system in different phases of the flight. There is large number of parameters and engine health monitoring and diagnostics going on. Most of it is not the responsibility of the aircraft manufacturer. Engine sends data to Rolls-Royce.
The first Airbus FBW airliner was the A320, introduced in 1988 (31 years ago), while on Boeing side it was the 777, introduced in 1995 (24 years ago). By now I don't think it would make much of a difference, if any at all.
If anything quarterly reports to shareholders who only care about the very short-term would be the culprit (or management teams whose bonuses only depend on the next quarter revenues). But numbers are stubborn and don't tell that story: the more recent the plane the safer it is. As such 787 and A350 are probably the safest airliners currently flying, followed by 777 and A380.
Many actual pilots would likely disagree. Shoehorning vastly different planes into the same type certificate can be dangerous. Convenient for pilots due to certification and recurrency issues, but not necessarily a good idea.
Do you really want a pilot to jump into a 737MAX who only ever flew the -100? I bet the memory items are very different if not also all the speeds and weights.
Is it because Airbus started its fly-by-wire development earlier?