"I was able to figure out part of the issue. It looks like if the photo is a JPG, only 7 out of 16 presets show up. When the photo is RAW, 16 out of 16 presets show up. Not sure why it happens this way though."
First, can you clarify which version of Lightroom you are using? You said you're using "the new Adobe Lightroom CC", but there is no longer any such program. The "CC" was dropped by Adobe for all of its apps many months ago, and so for Lightroom there is now Lightroom Classic (which is the latest version of the traditional desktop-oriented program that uses local hard-drive storage for the image files), and there is the cloud-centric version which is now simply called Lightroom.
From your description I suspect you are using Lightroom Classic. With the new profile/preset changes that were introduced in version 7.3, many presets can not be fully applied to certain file-types. The most typical example is when a preset includes the application of a specific raw profile, which cannot be applied to Jpegs, Tiffs, etc. Even some raw files could be affected if a preset includes a camera-matching profile for a specific camera type, and the raw file in question is from a different camera maker. There is a preference setting>Presets tab, which allows partially-compatible presets to be displayed or hidden...if the option is enabled, such partially compatible presets would be in italics, if it's disabled those presets would not appear unless the file is fully compatible.
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