The link you gave talks about impact of cuts on local authorities and particularly PTE▸ 's. Not clear what that tells us about the value of the scheme to the industry.
Now that is much more helpful. So it seems that, outside London, fare revenue has fallen.
Perhaps the most telling comment is:
There is no doubt, though, that the scale of these payments has had an effect on the bus operating industry in Great Britain, and on the services provided. For instance, on services where the great majority of passengers are travelling on concession fares, bus operators can set fares at a high level without any concern about passenger resistance ^ the local authority will pick up the tab.
On the on hand the concessionary fare scheme is providing some support to bus services, on the other hand it could be that high fares are deterring the ordinary fare paying punter and incentivising companies only to provide off peak services that do not meet the needs of the ordinary punter. If the latter is the case then we are in a spiral of decline.
There was also the comments about whether the scheme is sustainable given the rising numbers of those entitled.
The was also the comment about lack of competition with most buses owned by a few very large companies who do not compete.
None of this bodes well for the future of the bus industry.