This rumor makes it seem like DLSS will essentially be able to entirely close the gap between handheld performance and console performance. I am definitely suspicious of such a large claim. Though I do think DLSS may significantly close the gap, perhaps allowing next gen Nintendo ports of PS5/XBSeries games with performance set to lower settings, ray tracing turned off (despite this rumor claiming next gen Nintendo has ray tracing, I very much doubt that as it would be a huge waste of resources for a handheld), and minimal other changes needed. The idea, as this rumor suggests, that it will be on par with console graphics in every way, seems far fetched.
I understand DLSS 2.0 to be able to do about a 2x-3x performance enhancement. I would think that, along with running games at below 4k (after DLSS) plus 30fps for most games instead of 60fps and turning off ray tracing would probably be enough, as i said, to allow console games to play on Nintendo's handheld with no or very minimal graphical downgrades. If Switch 2 can even do this, rather than the much more significant claims of this rumor, that would be HUGE as it would mean AAA high-end graphics console games could get ported to Nintendo without much work done, just turn some settings down, turn on DLSS, and do the normal port tweaking you have to do as with any port between systems.