I think that there are several parts to your question. I'll just answer two.
First how can we encourage more people to use true sources?
My answer, we now ask for a source when a profile is created but we don't state at that point that unsourced familie trees from Family Search, Ancestry, Geni et al are not valid. We also accept family /personal knowledge which cannot extend back much more than a century. I think that this could be tightened up further
Your second point about pay to view sites. I don't think that comprehensive research can avoid their use. Indeed to turn it round, to use true sources one may have to use a subscription site. Transcriptions and finding aids (indexes) can be useful but one can't even see the image of a British Census on any free to view site.
I transcribe lots of wills from 16th and 17th century England. These are only available on pay a view site; they are a brilliant resource. The same pay to view site has the following sets of images for my local county,They are all primary sources. I don't think most are available elsewhere online However, though I am within walking distance of the archive these digitised records are not normally produced .
These are all for Dorset, Engalnd
Poor Law Settlement and Removal Records, 1682-1862
Poor Law Apprenticeship Records, 1623-1898
Quarter Sessions Order Books, 1625-1905
Tithe Apportion and Maps, 1835-1850
Convict Transportation Records, 1724-1791
Jury Lists, 1825-1921
Militia Lists, 1757-1860
Alehouse Licence Records, 1754-1821
Dorchester Prison Admission and Discharge Registers, 1782-1901
Vagrant Passes, 1739-1791
Land Tax Returns, 1780-1832
Calendars of Prisoners,
Crew Lists, 1863-1914
Electoral Registers, 1839-1922
Poor Law and Church of England Parish Records, 1511-1997
Bastardy Records, 1725-1853
Church of England Baptisms, Marriages and Burials, 1538-1812 (these are the images of the parish registers)
Church of England Marriages and Banns, 1813-1921 5
Church of England Births and Baptisms, 1813-1906
Church of England Deaths and Burials, 1813-2010
Church of England Confirmations, 1850-1921
Wills and Probates, 1565-1858
Heck sorry, I didn't realise the list was so long but it does demonstrate that there can be many different documents that may contain information about our ancestors .