It was the other way around, the feature phones were funny at the time so not supporting them would have made no sense. And iPhones and Androids had just been launched at the time so there weren’t actually lots of options for them.
WhatsApp was available for Blackberry, Symbian, and Nokia Series 40, and I’ve seen device support cited as an important part of its early success. It actually looks like Skype, AIM, and ICQ had pretty good support for various devices in the early 2010s too so I’m not sure that claim holds up.
A part of it was that they put in the effort to support featurephones. People with smartphones always had other options.
It was the other way around, the feature phones were funny at the time so not supporting them would have made no sense. And iPhones and Androids had just been launched at the time so there weren’t actually lots of options for them.
WhatsApp was available for Blackberry, Symbian, and Nokia Series 40, and I’ve seen device support cited as an important part of its early success. It actually looks like Skype, AIM, and ICQ had pretty good support for various devices in the early 2010s too so I’m not sure that claim holds up.