My question is: how efficient are these AIs really? Do they significantly improve a trader's overall profit and loss ratio, or is the improvement only marginal?
These AIs are just guides. If they are making enough money through the trader's way of trading, it's because they're there only to help but not they are the one that's entirely making the trades. Because if AIs are there to trade, then we won't be doing any trades anymore and let them work for our money and so we won't be bothered anymore of how to decide to make our trades win. But no, AIs/bots have been there already even the trend of AI came. It's not the actual AI doing the trade for us because many misconception are still thinking like that.
That's true, the question is if AI can make your trading easier and increase your PNL and yes it can. Got the referral code of the one the Kol I mentioned by Bitget called GetAI, did some analysis with it and told to run some analysis on the useless coin, guess what, it brought out core details like market sentiment, volumes, holders etc. This led me to place a trade and got profits.. surely it made the trade process faster.. but you've got to have some level of knowledge to know what you're doing at least.

I’ve even applied for the referral code to try it myself, so expect a detailed review from me soon.
It would be great if you have tried it and succeeded, and share your experience regarding the use of AI trading assistants. If it really works to produce consistent profits, even giving good suggestions for setting sell positions and stop losses. Those who make paid signal channels will probably be outcompeted.
I have never tried it, but have seen some videos regarding the use of AI to help traders analyze good trading positions. If it works, it is indeed something that helps.
I have . And shared my review earlier . But the product would need some updates but so far it's good and decent.. FYI you need to have a basic crypto knowledge for you to rely on AI though..