From what I can gather, they're not as adamant about shutting down ROM sites of their games. Somebody please correct me if I'm wrong.
Hundreds of PS3 games are available on PS Now, though they are unfortunately streaming only.
Dozens of emulated PS2 titles are available on PS4 for purchase, and some are even on PS Now.
PS3 and Vita stores remain open at the moment. PS3 has PS1 and PS2 classics, Vita has PS1 Classics and PSP titles.
Switch has a lackluster assortment of titles linked to their online service. Why only NES and SNES? Where's Game Boy? N64?
3DS and Wii U have tons of classic titles on their still open eShops, but most of them are overpriced.
Sony has work to do, but they seem to be handling things better than Nintendo. What makes it even worse for Nintendo is the sheer embarrassment of riches they are sitting on compared to Microsoft and Sony.
Adding hundreds more legacy titles from about 6 more unused legacy platforms would help Nintendo so much.
I think your argument tries to paint Sony in a much better light than they have any right to be in this regard. The main arguments are about availability and ownership for this (that is, not needing to access the internet and pay a subscription).
Sonys best legacy content offerings are on legacy platforms (similar to Nintendo). But even many of those content offerings are disappearing. Have you seen the PS1 classics offering on Vita recently? It seems every other day they are removing more and more games from the platform. Nintendo keeps as much of their content as they can on VC (sometimes some TurboGrafx titles go away), but Nintendo offers way more legacy platforms than Sony overall. The 3DS and Wii U combined offer NES, SNES, N64, Wii, GB, GBA, NDS, Game Gear, and TurboGrafx games. You can argue the price, but I'd argue the cost/value is too subjective on legacy content. Some people would pay more for SMB 3 than the vast majority of PSP offerings, despite it being 15 years older.
PSNow is essentially equivalent to NSO for this conversation. Both only offer legacy content via a paid subscription.
PS4 and their PS2 games amounts to 50 games where over 40 of them are third party titles like SNK fighting compilation games, GTA, and red faction. Sonys own games pretty much amount to only dark cloud, ape escape 2, Parappa the Rapper (which was remastered anyway), Rogue Galaxy and Jak 1-3. It's abysmal, really.
The only way Sony is better than Nintendo in any of this is that they don't actively pursue ROM sites like Nintendo does, but this is likely more related to Sonys legacy IP having less value overall and the fact that any time Sony has tried to fight against emulation they've lost. It simply isn't worth the legal fees for little gain. And, you said it, Nintendo's catalog could offer far more riches, so they fight harder.