Intel modems will never fully catch up to Qualcomm modems because of a few technologies/patents that are exclusive to Qualcomm.
In my opinion, it’s a shame that Apple isn’t exclusively using Qualcomm modems. Qualcomm’s modems outperform their Intel counterparts by about 15% at any given signal level, draw roughly 30% less power, and include a several technologies (which the Intel modems do not) that improve performance by using the assymmetrical paired antennas in the iPhone.
Because Apple thinks that they're asking too much for their patents and that the patents are asking for a percentage of the phone price. The more expensive the phone even if that is due to more memory or bigger screen, the more money Qualcomm makes even though they don't have anything to do with the components that contribute to the additional cost. Qualcomm is mad because they lost out on the half of the LTE modems that Apple is sourcing from Intel and that Apple is not using their processors instead of building their own. As soon as Intel modems catch up to Qualcomm and include CDMA for Sprint/Verizon, I predict Apple will no longer use Qualcomm. It would not surprise me if after CDMA goes completely away Apple does not start making their own LTE/5G modems or acquire a company.