If we look simply at network growth in economic terms, Bitcoin is only going to attract larger and larger sums of money. This halving epoch we now have institutional investors (ETFs) and once it has proven itself at that level, the next stage will be nations openly buying it.

So even if fees increase in fiat terms, so will the size of the transactions. Enough to take the market cap far, far beyond that of gold. Once bitcoin has grown to the point that its value has stabilised, there will be substantial demand for transacting in it directly and there will naturally be a lot more work invested into higher-level payment networks/solutions. Right now though, Gresham's law sees to it that most people are happier to hoard than spend and that's likely to be case until bitcoin is at least $10M/BTC