A leaker has provided further details about the Vivo X100 Pro+ or Vivo X100 Ultra camera flagship, which is expected to be launched in 2024. Based on a prototype, the triple cam equipped with 4.3x optical zoom appears to be quite versatile and can apparently reach ridiculous sounding digital zoom-levels.
Yes, that is one use case for pixel binning. Apple uses it to reduce noise in low light photos, but it can also be used to improve telephoto images where more data (from neighboring pixels) can be used to yield cleaner results.