I do believe that eventually sexual desire gets in the way. If you’ve formed a true friendship you genuinely like the other person and you have similar tastes, morals, values, etc. Assuming you’re heterosexual, nature is bound to take its course. Sometimes it can be ignored; sometimes not. I appreciate those who can remain platonic friends with the opposite sex because it’s always nice to get the other point of view.
What if there's no physical attraction? Would a lack of physical attraction mean that those desires would never surface? Likewise, do you believe that there are personality traits that could keep someone from ever feeling a sexual desire even though two people were similar in tastes, morals, values, etc.?