Based on all these replies I read, from newbies to Legendaries, I realised that this is something that no one thought of on bitcoin. At least, no one has a solution. Right now we can may payments really cheap, I had made a payment using only 300 satoshis. It took 5 days, but it did. The median is about $2. I've noticed that by paying 1 sat/byte (which is much lower than $2) can take about 1 day to get confirmed. So even if the median reaches $10, we can still make transactions really cheap.

Now, I don't know much about that lightning network, but I'm sure that not every bitcoin adopter will switch on using that.

The conclusion is that the $100k seem to be a dream that won't come true...