To recognize a high-quality conditioner, you should first and foremost check the ingredients and make sure that it does not contain any harmful chemicals such as silicones, polyquaternium, microplastics, parabens or sulfates.
Silicones are still found in many conventional conditioners and shampoos, even though they are entirely avoidable. Conventional hair care products are also increasingly being advertised as "0% silicone", with the most commonly used substitutes being even more problematic.