In the US we lost basically or entire 1890s census due to fire. San Francisco lost most of its historical documents in the 1906 earthquake and fires. The UK lost the 1931 census due to fire (and then didn't do one in 1941 because of the war). Millions of European church records have been thrown out. Often times these are the only record that someone existed at all.
We are now in an age where things can be easily scanned and archived, but they're are still millions of paper records that only exist in paper form in a filling cabinet somewhere.
That being said, genealogy today is 100x earlier than it was even 20 years ago. I have been able to find documents in minutes that took my grandparents years to find because they have been OCRd and are searchable online. However there is still a lot to be learned from old fashioned research, writing letters to and visiting city clerks hoping they may have interesting records about your ancestors.
I find genealogy pretty satisfying as a hobby and I recommend it to anyone who likes dipping their toes into multiple disciplines. You can go deep in document recognition, archiving, photo restoration, face identification, genetics/DNA, data models (GEDCOM), writing, community service (lots of archiving roles are volunteers at small governments or libraries). It is great way to connect with relatives, known or unknown, and scratches the problem solving itch for me.
It is a hobby/industry where the tools are mostly ancient and there is lots of room for "disruption".