A few weeks back, we had a chance to chat with Qualcomm executives and asked if any other SoC apart of the Snapdragon 855 will be able to support the already announced X50 modem. It turns out that the theoretically an OEM could make other chips such as 845 work with the X50 but it would be too much work and would make little sense.
In other words, it is not worth the trouble and Qualcomm is clear the first wave of 5G devices that it will start announcing next week will be powered by Snapdragon 855 and the X50 modem. Of course, knowing Qualcomm, there will be other modems and even faster application processors but at a later date.
Huawei is also expected to ship its Balong 5000 5G modem and match it with its Kirin 980 processors for its 5G phones in the course of 2019. It is not clear what the time to market is for these devices. If you are Apple, all you have to do is to twist AT&T's arm and make the company rename 4G LTE to 5Ge and claim leadership. This disgusting move is not helping the 5G initiative apart of helping Apple customers being cluelessly superior and AT&T claiming fake 5G leadership.
Naturally, the 5G modem will get integrated in the SoC but this won’t happen that soon and doesn't need to. Many manufacturers in the course of 2019 will continue introducing 4G phones alongside with 5G and the coexistence will continue in 2020 as well.
It took a long time for 4G to win over 3G designs and make them obsolete, especially in the mainstream and entry level market. 5G, as you can imagine, will start from the high and just as any new technology, will work its way down.