I can vouch for this - our company used to pay for additional promotion. They ended it back in July and now our posts aren’t showing up on people’s feeds right away, and overall traffic has plummeted. It’s like FB is punishing for not paying anymore.I have a small business as a side job. When I post on Facebook from my business page Facebooks algorithms are setup so basically no one ever sees it, even if they have liked my page. They made this change a few years ago as a HUGE money grab. Don't even get me started on the way they treat small businesses on Instagram.
Facebook has its own rules too - pot meet kettle.