Daredevil still has ways to learn Spider-Man's secret identity following the events of Spider-Man: No Way Home. 2022's colossal holiday season blockbuster, No Way Home ended with Doctor Strange (Benedict Cumberbatch) casting a spell to erase the world's memory of Peter Parker (Tom Holland) in order to stop an apocalyptic Multiverse-breach. There is, however, one man who could easily uncover Peter's secret in the spell's aftermath—and he's a really good lawyer.
Matt Murdock (Charlie Cox) is Peter's legal counsel in the movie after the latter is framed for the murder of Mysterio (Jake Gyllenhaal), and like Peter, he leads a heroic double-life as Daredevil. Despite being blinded by toxic chemicals as a child, Matt's remaining senses were heightened to superhuman levels, his sense of hearing even granting Daredevil a sharp "radar sense". These abilities make it much easier for Matt to uncover the identity of a masked hero like Spider-Man.
One aspect of Matt's hearing that has served him well as both a lawyer and as Daredevil is his ability to listen in on a person's heartbeat. This enables Matt to detect when someone is lying dues to changes in their heartbeat, but he could also very easily apply this as a tool of identity recognition. By being attuned to specific subtleties in Spider-Man's heartbeat pattern if the two were to cross paths in their heroic lives, this would give Matt plenty to go on in metaphorically unmasking Spider-Man's secret identity.
After being in close proximity to Spider-Man, Matt would need only be similarly close to Peter Parker to listen to the heartbeat of the tragically forgotten Wall-Crawler in order to recognize their identical pattern. Hearing also would not be the only sense Matt could rely on in uncovering Spider-Man's secret identity. Matt's greatly heightened sense of smell could also enable him to once again learn the truth.
In battling villains and common street criminals, Spider-Man would be bound to have debris like dirt, mud, water, small pieces of concrete, or other elements land on his body. As Daredevil, Matt would easily be able to detect the scent of such debris that almost no one else could on Spider-Man. Similar to matching Spider-Man and Peter Parker's heartbeats, Matt could then simply make the connection by being close to Peter and catching the scent of debris previously detected on Spider-Man.
After No Way Home, Charlie Cox is continuing ahead as Daredevil in the MCU, and given their comic book history as close allies it seems like a strong possibility for Spider-Man and Daredevil to meet and potentially even team up at some point. This could also be where The Man Without Fear becomes the first MCU character to learn the true identity of New York's Friendly Neighborhood Spider-Man after Doctor Strange's amnesia spell took effect in Spider-Man: No Way Home. Fortunately, audiences and Peter Parker himself can rest assured that his secret identity will be safe with Matt Murdock.
