How can you be so sure that the popular dating platforms behave ethically?

On all the most popular platforms the match algorithms are determining who you get to see. You cannot simply browse all profiles anymore and make a decision for yourself. This alone is enough to put it near scam territory.

There are various paid boosters users can buy to appear over of other matches, making it more of a marketplace than a neutral matching platform.

Plus, there is no incentive for platforms to match people into monogamous long-term relationships. A happy customer is a leaving customer.