I think it ultimately comes down to having to support another platform ads more work and risk then its worth.

For example theyd have to convince people to essentially break androids walled garden which means valve has to make sure everything they offer for android isnt malicous. Then there is the fact that phones are different specs, more testing, potential customer support … Its a whole can of worms, but valve would gain little.

Vavle is good at what they do, they have basically cornered the PC and portable PC markets already, i think not mucking around in an already monopolistic mobile market is a pretty wise business decision on their part overall.