Choppy video playback on videos shot on iPhone X

I have a 2012 Macbook Pro. I noticed that with any video shot on my iPhone X, the playback is very choppy in the "Photos" app. At first I thought it was because they were shot in 4K, but I have videos shot in 4K from my old iPhone 6s and they play back fine. Any idea why this happens or if it's possible to fix? I know this is an old machine but it's still pretty powerful.. has 2.7 GHz Intel Core i7 and 16 GB of RAM. Full system specs below.

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