The current obsession over lineage is no different from what's happening in the rest of the world and culture regarding credentials, credentials, credential, in the workplace, where they all want you to have either a certificate or a degree even though in the majority of cases, such "certifications" have almost no correlations with work ethic, actual troubleshooting skills or how well one actually does the job.
I have had to teach everyone that was brought on a job with their degree's or certifications numerous things about how to troubleshoot networks, routers, switches, computers, how to think logically, critically and technically, even though I've only taken classes and learned most of what I know from actually fixing said equipment.
The same is also very much true for the obsession only lineage in the martial arts. I have advertised to teach in the past online and most of the questions I got were regarding lineage. Part of my advertizing was emphasizing that if you wanted to really learn how to fight using real gung-fu, not just forms galore with no real world fighting applications, then contact me to learn more.
But despite that, almost all of them were still more concerned with my specific linage and could I prove it, getting various ranks and how often I gave advancement tests, etc..
I went back and forth with several of these potential students and ultimately almost all of them never bothered because, as usual with the entire culture today, they were more interested in getting a type of "college course in Gung-fu" rather than actually learning how to really fight, to work hard at improving themselves, gaining power, strength, physical, mental and spiritual skills that would vastly improve their health, strength, speed, endurance, toughness, longevity and more.
This is why I''ve had very few students overall, because most either do not want to work hard at all, don't care if they can ACTUALLY fight, as long as they FEEL they can fight and are more concerned with bragging to others about the lineage of their master or school than the skills they've obtained. To me this is utterly ridiculous, insane and waste of time.
I was taught privately by my first teacher who did learn directly from an Grandmaster that is now over 110 years old who was one of the last true students from the southern Shaolin Temple that was destroyed in 1928. So the "lineage" is about as authentic as you can get, but because I don't have some official looking document claiming that my teacher, or his teacher was granted the "authority" to teach or holds the official teachings, many people simply didn't want to bother even meeting and seeing what I can really do.
Several even said that they don't care how fast, strong, powerful, skilled or how much knowledge I actually have, if I can't prove lineage they didn't want to "waste their time or money". I simply said to this person "Then you are not really interested in true gung-fu, being an heir to that true knowledge, working hard to gain true skills or learning an amazingly powerful and effective art that can save your life in countless ways and improve your life on every level, so we're obviously not right for each other as I'm not interested in teaching people that are only concerned with the vanity of having some pointless certificates or bragging rights to some lineage that can't be proven either way. I could just as easily fake up some "official" looking document and claim it was from my teacher or the Grandmaster of the system and unless you went and spoke to the Grandmaster, you wouldn't have a clue.
So as I'm sure you can gather from my response, lineage has little to nothing to do with trustworthiness or credibility, nor with the skill of a teacher, his character, attitude, how good a teacher he is, the knowledge he or she possesses, etc.