Sterling is out of contract next year, the same as Jesus. Why would you think his transfer fee would be much different to Jesus's? Or even his wage demands perhaps.
It's more the total package. If Sterling is on £300k a week as is being reported, then I'm not sure he'll entertain Arsenal trying to sign him in the summer for £200k a week.
Whereas if Jesus is on £100k a week, then doubling your money is much more enticing than losing a third of your wage to move.