Qualcomm's biggest advantage in the 4G era was his modems. Qualcomm is the only chip maker that can combine a SoC and a modem into a single chip, combining technology expertise and intellectual property rights, and sell it globally at an affordable price.
This single-chip solution is hugely beneficial, resulting in a smaller, less complex, cheaper motherboard and more battery space. Consolidating everything on a single chip also results in power savings while the phone is active, as one chip generally consumes less power than two chips. Qualcomm users have been enjoying SoCs with built-in 4G LTE modems for years, and the company has taken that design advantage to market dominance. As a high-end SoC provider, Qualcomm is now virtually a monopoly: almost every Android flagship uses a Qualcomm SoC.
Qualcomm recently released its flagship SoC for 2019, the Snapdragon 855. However, the company spent hours gauging it If you're upgrading the Snapdragon 855's 5G compatibility, there's no 5G mmWave modem on board. The 855 will have LTE as usual, but 5G phones will require a separate modem. Qualcomm will lose its single chip advantage for 5G. As explained above, this means less battery and more power consumption.
We've already gone through the entire routine of "first generation network hardware". When we switched to 4G, we got the first batch of new 4G hardware with the same discrete modem compromise that we'll see with 5G. The most famous example was the HTC Thunderbolt, the first 4G device in Verizon's network. Qualcomm's Snapdragon MSM8655 SoC (prior to the simplified model numbers!) Was used with a separate Qualcomm MDM9600 LTE modem. The Thunderbolt was a disaster, because it contained all this new 4G hardware with only 1400 mAh battery. It was thick, hot, slow, faulty and had a terrible battery life. The Thunderbolt regularly keeps lists of the "worst phones ever" and an HTC employee even apologized for making the phone. New network hardware can be a disaster if you do it wrong.