Is it wrong to make others think you are more spiritually blessed than they are?
Yes, it is wrong. Scripture says no one should be puffed up one against another, and Paul warns that you cannot give someone the impression you are better than they are or more spiritually blessed. Such pride in spiritual status is carnal and infantile and is the problem Paul addresses.
Les explains that the Corinthian congregation had people getting puffed up, with some claiming importance because they followed Peter and others because they emanated the apostle Paul. Paul transferred the lesson to himself and Apollos as a figure so they would learn not to think of men above what is written and not to be puffed up one against another. Les points out that you cannot get puffed up and give someone the impression you are better than they are or more spiritually blessed. He calls such behavior infantile and carnal, and notes that while things themselves are not wrong, the issue is priority, since believers are left here to bring honor and glory to God.
And these things, brethren, I have in a figure transferred to myself and to Apollos for your sakes; that ye might learn in us not to think of men above that which is written, that no one of you be puffed up for one against another.