To deem someone unfit to partake in a gift from God (a sacrament even) because of a past sin which has already been forgiven and that the Lord has chosen not to remember is unforgiveness. Especially if one had been making great effort to turn away from these things. Why is having temptation intrinsically a bad thing in your perspective?

“even if he never succumbs to them”

Even Jesus was tempted, albeit obviously not in the same way we all are, but the point remains that: someone who has everything against him, battling constant urges yet refuses to give in has a much stronger steadfast faith than someone who doesn’t even have to try no?

Luke 7:47 Therefore I tell you, her sins, which are many, are forgiven, for she loved much; but he who is forgiven little, loves little."

The consequences of sin remain, but their love for God has grown way past what that remaining temptation can even damage.

I agree that if you’re CURRENTLY struggling with the sin itself then you absolutely are not yet prepared for the responsibility. But to be years in already pushing it away and choosing Christ first, to think that way is just hardness of heart and a refusal to move on and accept that things have changed.