What is the ruling on looking at an elderly non-mahram woman according to the madhhab of Ibn Taymiyyah, and does his general ruling against the impermissibility of looking at a non-mahram woman absolutely include both elderly and young women?

There is no explicit transmission from Sheikh al-Islam Ibn Taymiyyah regarding the ruling on looking at an old woman, except what Ibn Muflih narrated from him concerning the permissibility of looking at someone who is generally not desired. It is understood from Ibn Taymiyyah's words that an old woman who no longer expects marriage is permitted to lay aside her outer garments because the potential for mischief has ceased. This implies the permissibility of looking as long as the uncovering is permissible. The majority of scholars permit looking at an old woman without lust, based on the Almighty's saying: "And as for elderly women past childbearing who do not expect marriage, there is no blame upon them for putting aside their outer garments while not displaying adornment. But to modestly refrain is better for them." This is also because the reason for prohibiting looking is absent in her case. The Hanbalis appended to the old woman anyone who is not desired, specifically permitting looking at their face.