You can get a dog from a breeder and make a huge mistake doing so. You can get a dog from a shelter and make a huge mistake doing so. Outside of avoiding irresponsible/unethical puppy mills I think the biggest decision and the thing people should spend more time thinking about is what they want in a dog. Figure out the traits you desire, the breed behavior attributes that fits your family lifestyle, the behaviors the breed was created for. Once you have that figured out you should consider adoption versus reputable breeder.

For many the cost alone will mean adoption or breed-specific rescue groups. But for others it means finding the breeder that checks the boxes for what you desire. If you adopt don't do so based on looks alone or even a few playful minutes in the shelter yard. Understand the breed(s) that are in the dog you are adopting. Understand the trainability and the instincts you are bringing into your family. Irresponsible adoption can do more damage to the life of the dog that was "rescued". Too many are adopted, don't end up being the cute and playful thing the family saw at the shelter, and then relegate the dog to the backyard and a doghouse.

Responsible breeders are the ideal option if it is affordable for you and you really know what you are looking for. You can have more confidence in how your dog will turn out, have lower possibility of breed-likely diseases, and you may even get to meet the parents and get a look at their behavior. Those things are often a crap shoot with an adopted dog.

Both paths are great. But trying to shame somebody else's chosen path is lame and uninformed.