There is no doubt the newspaper print industry is having a hard time of it.
Few people have time to read in-depth news articles in print and a brief synopsis of the main news events is freely available on-line or broadcast from many media sources and will be more up to date than any printed copy and is perfectly adequate for many.
With declining print sales, getting a revenue stream from on-line editions has been a challenge for the industry and there have been a number of different approaches ranging from total paywalls to restricted articles to voluntary contributions and completely free but dumbing down.
Restrict the readership with a paywall and advertising revenue declines.
I don't know how successful the various revenue models have or are likely to be and I would think it's still in a state of flux. Your idea of paying per article may have some merit but you would be paying for one article unseen which may amount simply be a rehash of something already read elsewhere or simply just be froth with no in-depth journalism.
Perhaps a model where you pay for 24hrs access to the on-line edition when there was something particularly newsworthy happening and had no wish to subscribe on a more permanent basis is worth some consideration.