If you have a lower end PC and are impatient for PS exclusives then perhaps you can be converted.
If you have a higher end PC and are patient for PS exclusives then probably not.
If you have neither at the moment and are yet to jump in, then buying a PS5 is likely a more straightforward prospect and retaining timed exclusivity for flagships will reinforce that.
Then there's those that already have PC + consoles, many people who previously had Xbox + PC -or- Xbox + PS + PC; have now dropped their Xbox as it makes little sense to keep it around. If Sony go day one PC for flagship titles then many may drop their PlayStation as well. Sony losing a PS-owner means losing someone in their ecosystem, it may mean losing a PS Plus sub and it will mean a smaller slice of the software pie at retail. And it's not always a case of someone selling their current system but not upgrading to the next one in the next gen. Plus if someone drops their PS console, then they're no longer going to be purchasing any third party content for which Sony gets a cut on their platform; as well as third party mtx cuts.
They also need to keep an internal financial incentive to prioritise quality because something is directly representative of the brand, the console and the ecosystem. It's a feedback loop. I also think having studios 100% focused on a single spec is beneficial, sometimes inspiring technical creativity to raise the bar. If you're having to do everything with a bunch of other hardware permutations in mind as well as likely having to work at a higher level programmatically then some things may not be possible.
I think Live Service/Multiplayer should be day one as should smaller scale stuff and remakes/remasters, VR stuff should be day one too to help the format, but flagship first-party single player experiences need to retain a 12-18mth window imo.
It's not just a case of moving from PC to PS5 or vice versa, but loads of different situations adding up. I think on balance maintaining a timed exclusivity is the better option and it's much safer in the long run, cause once the genie is out of the bottle and if things start to slide too quick, there's no putting it back in.
Just selling more (SP) software doesn't mean more money, you have to factor in retooling studios to work on PC in parallel and the increased upkeep of that, many sales on PC will be lost sales on PS5 which means less money from the sale and of the new sales you gain from an early release catching the hype cycle, you're getting a smaller piece too. And while doing this you're likely losing console sales going into the next gen if they already have a PC + PS this gen and you're disincentivising newcomers who are on the fence, not to mention risking a steady ecosystem and subs decline overall that may require a backstep which would be a major PR disaster.
It seems like a lot of faff and high risk for a small uptick in sales and little guarantee in overall financial outcome.
Sony are making the right decision, but Herman Hulst summarised why poorly.