It's actually entertaining, but as a (rather long) summary (mind you that I'm doing this from memory)

• Clip of an LTT employee taking a jab at GN and HUB while presenting their labs by saying something along the lines of "our reviews are more precise because we retest everything everytime", which is a lie.
• Lots of stupid and big mistakes that should have been noticed by anyone looking at the data, like the 4090 being 300% faster than the 3090Ti just in one game/test, when it should not.
• Many of those mistakes not being corrected at all, and if they are, they are done in the laziest of ways and as barebones as possible. For example in the previously mentioned 4090 review, they only "corrected" the aforementioned problem in a comment (which was not even pinned until the community complained), but ignored other problems that were present in the video.
• Many other vids are so lazily done that even if they know they have made a mistake, rather than reshooting it (the whole vid or just that fragment), they will just include a callout in the vid. Not a problem if this were in 1 or 2 videos from time to time, but as of late, it is a frequent problem.
• Conflict of interests/Biases. In a video GN put out as an example, LTT implied that all Asus products are good. A more egregious example is that they like Noctua products so much, that even when their own testing shows that the CPU is thermal throttling with Noctua products, they will still recommend it over anything else.
• Delaying a review of an AMD cpu because his results weren't similar to the rest of reviewers nor AMD's numbers. He didn't want to be "the black sheep".

And now the 2 worst things:

First, they tell you about a mouse LTT reviewed in ShortCircuit, which they essentially bashed because it had very poor gliding (funny because they then chose that mouse anyway for some kind of event)... just to discover that they hadn't taken the plastic sheets off the pads. LTT, of course, rather than amending the error, decided to blame the company for making them "hard to see" (like any other mouse company does, duh).

And the worst of all. They did a review on a prototype of a waterblock done by an indie company/startup called BilletLabs. It was their best prototype so far and the only unit they had, which was going to be used to give it to other reviewers and then continue working with it themselves (this is important). This waterblock was only tested to work with the 3090Ti, but LTT, lazy as they are, decided to do it on a 4090 anyway. Surprise surprise, it didn't fit well at all, so their video was, essentially, pure bashing of the product because, as it turns out, it is hard to fit a waterblock on a card it wasn't designed to work with. And of course, it had poor performance as a result anyway. After community backlash, however, Linus decided to double down, saying that the product was, essentially, garbage anyway (not with those words, but it's easy to read that when he says that he would not recommend it to ABSOLUTELY nobody, no matter how well it would perform), Luke seemed to be... unwell during Linus' rant, btw. He also said that he would not be wasting money on having someone shoot a proper review of a review HE HIMSELF BOTCHED. So basically, he bashes a small company, all while doing a shitty as review even my grandma would do better and then he is out of fucks to give. Not content with that, BilletLabs asked a couple of times for the waterblock, so they could, as said, give it to other reviewers and then keep on working with it. LTT agrees to give it back. What does LTT do, however? They fucking sold it at an auction during the LTX. THEY FUCKING SOLD IT WHEN THEY WERE SUPPOSED TO GIVE IT BACK. The best (and only) prototype of a startup made by 2 dudes and, not content with bashing them, they fucking sell it at an event to which competitors were in attendance. The fucking audacity.