You must have never shot with the guy or GH5 to say something that simple minded.
IBIS in the GH5 was a game changer! And 10-bit internal recording brought pro level capture to the masses. Maybe if your just recording for YouTube, you may not appreciate the quality gained, but you'd have to move up to the Sony FS7 in order to get 10-bit 4K.
So let's please stop with the no one has HDR 4K sets argument. I've had one for over two years. Maybe your circle doesn't have one, but you always should capture footage in the highest quality your budget can accommodate, and the GH5 has that in spades.
Additionally, the OP states interest in photography, but he didn't state what kind. I shot portraits and weddings for years using APS-C gear without complaint. And if he decides to shoot sports, there isn't a full frame camera made that will meet the requirements of that genre. That's where 14 fps and the extra reach of the APS-C Nikon D5 best full frame every time.
And guess what? The 6K photo mode best the Nikon D5 in reach and frame rate! Then there is the GH5's focus stacking feature, post focus feature, time lapse feature, direct to web image transfer with the Panasonic Image app. Hey, you know what? It sounds like the GH5 is a fantastic hybrid camera after all!
Do I own one? Nope. But I have no problem recommending one for the OP over anything else.