I think that is a YES and NO sort of thing.
YES ... there were clearly 7 real churches in those 7 real cities in a real geographic region that is now Turkey. The fact that they were near where John was imprisoned, that they knew John and John knew them, that the order in which the churches are addressed form a Travel Loop (circuit) around the geographic region, that they were all being persecuted at the time ... cannot be ignored given the context of Revelation.
NO ... the profound symbolism (7 lampstands = the complete church) (7 spirits = the 'complete' Spirit = Holy Spirit), and the universality of the issues they were facing ... point to a message TO them but FOR the entire church in all times.
Think about Jesus giving the Sermon on the Mount. Jesus was speaking to different specific groups of people gathered together that needed to hear different things to address their specific First Century problems (Roman oppression isn't the problem it once was) ... but the TRUTHS contained were for us because those TRUTHS were universal. We still face troubles and still struggle with sin and still need a savior.
So, too, the church [that means US, the people] still face issues in the world. We are still prone to falling into the same pitfalls that the seven churches in the letter fell into. Therefore, the advice from Jesus TO them is just as relevant FOR us.
So just like the Sermon on the Mount, it was TO THEM and FOR THEM and it was TO THEM and FOR US.
That's what I think all of Revelation is.
The whole focus on some "big bad" is going to happen in the FUTURE and will the RAPTURE come "before", "during" or "after" the "big bad" misses the whole point of Revelation. BAD things happen all the time in life, especially if you are in the Church ... what you need to remember is that the "bad" lasts a short time, Jesus wins, and then the "good" that follows lasts a VERY, VERY LONG TIME! That is the message we are supposed to take away (not a timeline of the future).