Because of this I would think Leclerc sounds better for them than a T-90.
It also helps them to reduce the need for manning their tanks and could use the same ammo like the M1A2s they already use.
And there is already the tropicaine version in use with the UAE so they have experience with making the Leclerc suitable for the Saudi environment.
Maybe the T-90s are just somme funny new toys for their National Guard which seem to be more there for countering their own army than for giving additional strength to the defense forces.