[Warning: The following contains SPOILERS for Resident Evil Village.]
Resident Evil 7 took the series in a new direction, altering its camera perspective and gameplay focus, as well as creating a new storyline in the RE universe. It introduced two major new characters, Ethan and Mia, who were extremely important during the events of RE7 and its sequel, Resident Evil Village. One of the core storytelling gimmicks of these games was hiding Ethan's face from the player throughout the entirety of both, but Ethan ends up dying in an explosion at the end of RE Village. Resident Evil 9 will likely pick up where Village left off, and it doesn't need to include the previous games' first-person perspective to hide Ethan's face any longer.
Even in the rare instances when the camera points towards his face, players never find out exactly what Ethan looks like. Perhaps this is meant to heighten the sense of immersion while in first-person, allowing players to more easily project themselves onto Ethan, but it could also be to hide the fact that he's been infected by RE7's mold the whole time. Still, even with the regenerative abilities Ethan's mold body grants him, he is almost certainly dead at the end of Village, so RE9 could once again return to third person.
Players will most likely be controlling either Chris or Rose in Resident Evil 9. In Village's ending, players get a clear shot of the grown-up Rose's face, meaning RE9 would gain nothing from hiding it from players like her father's. Chris has been in many Resident Evil games before, and he shows his face multiple times throughout Village, so there's no need to hide his either. Players do control Chris briefly in first person at the tail end of Resident Evil Village, but this could have been done only to avoid a sudden, awkward transition into third-person gameplay.
Why RE9 Likely Will Be In Third-Person
RE Village also focused on making gameplay more combat-centric, which could translate better to a third-person perspective in RE9. The wide camera views in RE4, RE5, and the RE2 and 3 remakes allowed players to see more enemies at once and made room for flashier combat techniques, like kicking enemies once they're stunned. This could potentially mesh well with Rose's bioweapon-like powers if she becomes the playable character in RE9, especially since those powers were left ambiguous in Village. Perhaps Capcom will give her combat abilities never before seen in a Resident Evil game - ones that could be shown off more clearly with a third-person perspective.
It's still possible Ethan somehow managed to survive the explosion or that Capcom would simply like to maintain a consistent perspective throughout this would-be trilogy, but there's a solid chance players will one day be looking over Chris or Rose's shoulder in Resident Evil 9.