The FTSE 100 index is today at around the same level it was in 1998. 13 years seems like a pretty long time to me.
25 years is long term. 13 years is not long term.
You've shown another error in people's emotions. People take snapshots and use it to prove their point. Clearly worldwide stock markets are crashed - and may not be coming back anytime soon. Or they may come back tomorrow. But when the do come back, it's been shown they come back fast - they will recover substantial portions of their losses in one day. People don't believe that. They'll believe that markets are low so they'll go elsewhere for now. Then they believe that they'll see the rebound coming and get in then. Except it'll be too late - the markets will return all in one day, or in 3 specific days over a year or two. It'll happen on a Tuesday and when you wake up on Wednesday it's already too late. the academics have shown this, few actually choose to believe it. Instead, they'll use stuff like what you've just done to counter it.
Frankly I'm not in a position to defend this, but there's lots of academics that have shown repeatedly what I'm suggesting - it's there for the reading. And it's not as easy as just stocks, it's as easy as a very specific, diverse range of investments. If you were all in in stocks (like many people), yes, things suck now but will be better long term. But the correct way is to have a diverse investment strategy (and diverse is not what most people would define as diverse, there's again a specific mix) so that while the stock portion overall is low right now, the overall investment mix right now is doing reasonably well. And when the stock returns, other aspects won't do as hot - but overall there's consistent returns over the long term.
If you want to have the highest returns and lowest risk over the next 25-30 years, what you need to do is clearly defined already, the information is readily available for anyone willing to spend some time reading. But it does not involve taking 13 year snapshots and saying 'see! I could've made more money doing something else'. It involves NOT doing that.