I really think that there is no one right answer to this question - there is no one best polish. That's one reason why there are so many, because they each have different attributes that correlate with the needs of different techs and clients. The key is figuring out what's the best polish for you and your clients.
For some techs/clients, a polish being hypoallergenic is their number one concern - so CND Shellac is best for them. For some, having a huge range of colors and effects is important - Maybe Gelish or IBD is for them. Fantastic education and training? Try CND or Jessica Geleration. Huge market penetration? OPI. Matching rnp? LeChat or OPI. Fashion forward colours? Artistic Colour Gloss. You see where I'm going with this. Then there's the shine, the longevity, the ease of removal. Then add in whether the product is cruelty-free or vegan, made in the USA/UK, whether you have an existing relationship with the vendor, whether they have a spa line, and of course, the customer service and the price.
Rather than figure out what others think the best polish is, figure out what you need your polish to be, and then find the brand that delivers that. It may not be what someone else would have chosen, but it will be what's best for you.