There's only two problems with that line of logic.
We'd have to assume that publishers are not already doing this, and they are doing this as we speak. PSPlus games are often relatively recent titles and they're available for free for PSPlus subscribers - I don't see PSNow games being available via a subscription as any less probable.
Moreover, we'd have to assume that PS3 games will continue to be released years into the future, which they won't - the system has maybe 2-3 years of air in it left at best. PSNow, as Guild mentions, is a "virtual console" sort of deal with cloud streaming used as a distribution medium - it's not designed for brand-spanking-new productions anyways.
We'd have to assume that publishers are not already doing this, and they are doing this as we speak. PSPlus games are often relatively recent titles and they're available for free for PSPlus subscribers - I don't see PSNow games being available via a subscription as any less probable.
Moreover, we'd have to assume that PS3 games will continue to be released years into the future, which they won't - the system has maybe 2-3 years of air in it left at best. PSNow, as Guild mentions, is a "virtual console" sort of deal with cloud streaming used as a distribution medium - it's not designed for brand-spanking-new productions anyways.