I was away doing stuff until recently, but just a few friends I have in the industry working on games for both platforms and a few other insiders I know. More than one source. The basic gist of what I've heard is the PS5 is really good to work on for games exclusive to it, but in practice the specs kinda' get weird for multi-platform games. If multi-plat the usage of PS5's SSD systems does help a bit, but not to the fullest, and I've heard some dev friends talk a bit about the struggle PS5 has for 1080p games running 60fps still, while Xbox X doesn't have the same problem and can push above that even in most cases. Of course, this is a small selection of people I've talked to, there's more to it, but I hear something that's going to make this generation a bit interesting is the PS5 & Xbox X's focus in other areas are going to make multi-platform games "interesting" this generation, to the point we may actually see less of them and far more games coming to one platform or the other (plus PC), as it's actually kinda' hard to make a game optimal for both platforms due to where they're a bit differently focused.
But again, this is coming from the small pool of developers I've heard this from, there may be unique challenges to the games they're specifically making in this area and that isn't lost on me.
That said, I am going to dip on this as I just like sharing a bit of what I hear, I'm not super invested, but I knew something I could share could make this discussion a bit more interesting to where current feelings lie. I can promise you I'm not saying this based off of nothing, There's probably more on the tech side specifics I'm spacing on here/don't fully understand myself, if I'll be honest. But things will be reflective here when both consoles are out and multi-platform games are out there.