There is absolutely nothing independently governing and monitoring whether performance is correct on ads. It's all done in private, and you're forced to compete against SEO and many other things to succeed on a daily and even minute-to-minute basis.
This is the real price of a constant threat to Net Neutrality, and allowing one monopolistic company to dominate mobile devices, web browsers, search results, and the largest video service on the entire Internet.
Their plan to corner and manipulate what everyone's freedom of choice and to secure their funnel of permanent revenue is considered cute to investors, but no one realizes how bad this will get in 5 more years.
Of course the numbers are fudged when you consider how they've turned analytics on their once very useful platform into a confusing mess, and when they announced that they were going to retire the system after it has killed off competition, because they can simply gather any analytical report they want privately from their web browser.
Public front-end statics are no longer trust worthy because they can be manipulated to drive platform revenue and engagement. The best and most accurate stats are provided only internally, to executive leadership that owns platforms.
Because we now use them for email, video views, browsing, phones, etc, they have key insight that can even be used for corporate espionage, your ideas can literally be beaten to market because your virtual assistant caught you mentioning keywords then reported you applying for your patent and corporate loan.
Most people have no idea about how bad this all can get. We'll find out soon enough though.
When ad revenue drops on platforms, the platforms simply reduce organic visibility which drives the need for regular ad spending for companies in order to remain visible on social platforms... AirBNB is riding a wave of prior popularity and name recognition, I guarantee they will go back to a certain point of obscurity at some point because they reduced their ad spend, and then be forced to promote heavily as they did once before.
It's all creates a new cycle of financial deception and manipulation on platforms. For very profitable companies, advertising is usually manageable, but for startups, for small business, and for independent creators, this practice is devastating financially, and fruitless on top of the financial loss of paying for promotion. These platforms also made promises to woo users based on free organic growth, which somehow conveniently disappeared due to covert and convenient EULA updates over time.