I checked the PSN store and eShop rather recently, since I have not checked them in a long time.
PSN.. it is very unresponsive and slow, the eShop was a lot more responsive and easier to navigate (I was confused on PSN, on what I was clicking).
When it comes to online, Sony seems to shove it in your face (when I booted my PS4 and the PSN store today for the first time in about a year the first thing I saw in the featured section was a page that told me I should sign up to PS+, after some time that went away and was replaced by what I thought was a more appropriate featured page) and as for Nintendo that did not seem to be the case, sure there is a section dedicated to Nintendo Online but it's not as shoved into your face.
The curation of the stores is very different, the way Sony does it is that they have dedicated pages on PSN that tell you about the game (Sony's way of selling you these games), where as with Nintendo they have a dedicated news section on the N/S which is what they use for Curation and highlighting certain games while also talking about them.
PSN has a page dedicated to video games devs recommending games on the PS4, one of the devs is Cliffy B., I do find it funny how it mentions Gear of War on his thing, the main issue is how on his page it has a link to law breakers and if you click it, PSN will basically tell you that it doesn't exist. If we ignore that I am impressed with how Sony handles that page since they do have a number of well known game devs on there.
So PSN does seem to have some very impressive curation going on, but the problem is that this also limits what can/will be shown to you, for better or worse. Assuming that you liked a certain game and that dev made more games or something but you didn't keep up with the dev, then you likely would not know about a new game of theirs if it released on PSN. N/S does seem to have something that fixes this though?
On PSN there is a section dedicated to you and what PSN recommends to you (what it bases it's data off I'm not 100% sure, but I do know that PSN does keep tracking of your playing habit though and even give you a yearly report about it) and it's not that good. For some reason it was trying to sell me on Madden and NBA2K (I am not a fan of those sports nor do I play sports games), I think I once played Fifa on my cousins PS4 years ago and if it's basing it off that data then there is clearly an issue with relevance. Also PSN seems to have no issue showing you both the base game and additional bundles so you will not just see one listing on PSN, on eShop how ever it seems like you are only shown one listing and that is either for the bundle or the base game (the base game has the bundle option in it's DLC section).
For me the eshop seems as bare bones as it gets (and funny enough not even EGS can do that, and from the looks of it even EA origin has something like a trending section).
It did not look like eShop has some form of recommending you games based off what you have played (so you won't see something in a games page about other games that are similar). If you are an indie it looks like eShop will give you exposure in more ways than you could on PSN. On PSN unless you are one of the "choosen" indie games then Sony will not really bother mentioning or showing you (hell PSN doesn't even have a section dedicated to indies, the best I could find was a "unique" section, since that is the type of genre that PSN thinks indies are. And Indies may not 100% be a genre but from what I saw there did not seem to be anything on PSN that highlighted indie games, other than maybe the devs recommendation pages). On eShop, the way that more medicore (aka if you are not an indie darling, maybe hidden gems can also be considered medicore) games stand out is by being a part of the recent releases. upcoming releases and discounts.
There is more that I want to talk about but I will leave it here, have any of you see similar issues with PSN and eshop? I feel like Sony introducing something like the live reccomendation feature on Steam is way out of the question on PSN (especially considering how Sony themselves also pay money to promote certain games and if users can all of a sudden "ignore" that game, then that would be bad for busniess)