It's a good idea, but I think it will depend on Spartacus' catalog and country coverage.
I think that to the current PS Plus and PS Now+Plus bundle Spartacus mainly adds an intermediate tier, which seems to be PS Plus+PS Plus Collection+download only version of PS4+PS5 PS Now. If the second tier is this one, they since it wouldn't have streaming they would be able to offer it worldwide and would grow the userbase a lot.
But they also may increase a bit the countries supported by PS Now's streaming tier, and also could improve their catalog including more important games -maybe not all their 1st party games- closer to their release -but not being day one, maybe a year or two after release-.
If they have this improved catalog and/or country coverage, then I think the digital edition will be more appealing for many people thanks to Spartacus. If not, I have my doubts.
I'd like to see what is the best way for Sony to offer something akin to "Gamepass" without cheapening out their own game offering or consumers to call it "watered-down" Gamepass. They are between a rock and a hard place because Microsoft just has that much money to operate without much revenue from Gamepass only to grow their install base.
I can't see Sony offering their exclusives even after 1 year of being out in the market. The only thing I can see Spartacus having of value is if the games don't leave their library, but then again, licenses must get expensive to keep when some games will be on their catalog only to fill space after some time.
I think what Sony could do is first to include most -pretty like not all, because they want to continue selling games- their old games on Spartacus, those who already completed their sales cycle. I also think they keep adding very old games to the service, and to combine it with not too frequent additions (maybe once or twice per year) of big games that are only 1 year old plus some smaller games (mostly indies) added day one.
We also have to see what exactly are the 'extended demos' that Bloomberg mentioned for Spartacu's 3rd tier. They may be only these betas or demos that from time to time some publishers release and are tied to a subscription. But they could also be a long demo (1 or 2 hours long?) available day one of any game released on PSN, or at least from their 1st/2nd party games or main 3rd party exclusives.
So you'd get:
-To include most Sony old games included in Spartacus, many are missing in PS Now
-Most Sony games would be included there once they complete their sales cycle (around 2+ years after release), but once or twice per year they'd include a big game that is a year old or so (as they did this month including TLOU2)
-Extended demos (maybe 1 or 2 hours long) of at least all their 1st and 2nd party games, released the same day than the games
In any case, PS Plus has a huge amount of subscribers, plus some more from PS Now and I assume this relaunch and rework will bring many more even if they don't improve its catalog significantly with newer PS4 and PS5 games. I think they don't have a big pressure to highly change their plans, I think Spartacus more than a huge change will be some tweaks, reworking (merging PS Now and Plus into a single service with multiple tiers) and minor additions (extra legacy platforms like PS One and PSP for PS Now, increased PS Plus collection now also available in PS4 and maybe merged with the dowload version of the PS Now games, extended demos) to what they already currently have.