I also think this is the right time for Salah to leave. There will be a new cycle taking place at Liverpool with many big changes after Klopp leaves. Besides, Salah is losing his passion for playing football. We can see this through Salah's current performance at Liverpool recently, and his gradual loss of influence on Liverpool's attack.
Age 31 is no longer the age when a player is in his prime, signs of a decline in performance are understandable. Without much motivation to play, money will have an influence on Salah to move.
Yes Salah' contract duration is until 2025, so why would Liverpool not be able to ask a high transfer fee or why would clubs from the Saudi Professional League not pay a lot of money for him? The Saudis don't care and they would still pay a lot, but times have changed a little bit. The global interest in the Saudi league is decreasing again and this big hype when Ronaldo played the first games there is gone. I can't see where people are still biting their nails waiting to see how Ronaldo scores a goal in the Saudi league. I believe that the SPL officials were hoping for the hype to endure for much longer.
Ronaldo was the player with the biggest social following existing on the planet and yet the interest is decreasing again. Salah could draw some attention to the league again, but really how much will it be worth for the league as a whole? I think that the SPL officials are learning and adusting their expectations and willingness to pay these extraordinary fees and salaries.
Salah will probably still be able to make a lot of money from a transfer, but who knows what his intentions are and whether there have been made agreements already back when the rumors were going around. Nobody knows whether there are contracts with an SPL club already signed.