As for the decoding performance of Tiger Lake chips in NUC 11, only the i5 and i7 models have two VDbox(fixed-function hardware decoding ASIC). So the i3 model with UHD graphics may not compete with the Xe graphics in some heavy workloads, even if they are all Gen 12 graphics.
See the num of "Multi-Format Codec Engines" aka VDbox:
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