Well if you are going to make me spell it out, the biggest problem with HID in any form is the huge inefficiencies they create. Too much power going in, a huge percentage of which is just converted to heat. At least for me in the midwest USA, you end up paying twice. Once to light it, and once again for your AC system to suck out the heat.
These problems are even more difficult in a small tent.
And you can't just dim them down to 30% if you need to. You are moving lights up and down, and that's not easy to do for a new grower in a short tent.
Then there is the spectrum. Very bulb dependent. If you are like me, you end up buying and trying several bulbs to find the sweet spot. I have found that the eye hortilux
is the go to bulb for veg for example, and that bulb alone is $230. Add in all the extra electricity, and in one grow the LEDs are cheaper. And you still have to add in a flower bulb to the cost.
If you want to experiment with Far Red or any form of UV, that's more lights you have to buy and cram into the tent.
If the heat from the HID forces you to a mini split for the tent, or more AC for the lung room - well... $$$
Then there are the hot spots and wildly uneven par across the 5x5 area. Bar lights kick the shit out of HID for light uniformity.
If you get a tall plant that shoots up into the light, with HID they will literally cook. Not so with LED. Time and flexibility to make adjustments without plant damage win LED. Easier for a new grower.
There's more, but I'll stop here. I'm not saying HID is bad - I run them. But if I was a new grower and could buy any lighting today, I would not start with 1960s technology. That just doesn't make sense to me. But you know about opinions and assholes...