No but neither did Mr Knightly beleive that people shoudl (except for the Coles it seems) have the opportunity to rise out of their class.. at least to judge by what he says about Harriet in the earlier chapters. Pretty much the only way a woman could rise was by marrying someone of higher status. If For soem reason Emma had taken a fancy to one of the Martin girls (or the old writing master's daughter) and decided to "bring her out" into good society, he would presumably have said just the same thing.. leave her in her own sphere.. Im just pointing out that by modern standards Mr K is just as much of a "snob" as Emma is siad to be.