There are opportunities in bull and bear markets. Also, has the $SPY ever gone to $0? If you have the belief that it will, well, when that happens, we are all screwed. No point thinking doomsday.
But let's step back and calculate suppose you got into $SPY in 2007 at 155. If you had kept the $10K in there, it would be worth $20K today almost. However, if you had kept adding money to it each year, your return would be massive. As you get older, you move from more index holdings to bonds, which guarantees you to hold your money. Another method is dividends, if you had AAPL shares, suppose 1000 shares @ 0.50 per quarter, that's $2.00 a year on 1000 shares, $2000 a year. If you had a family member who doesn't work and owns all the shares, in Canada, that would be up to $60,000 each year you can earn tax free.
I don't hold any stock, although I believe it is safe to do so, I currently only own 2 shares of TSLA as I wanted to be eligible for the class action lawsuit if there ever was one. I only trade options and I believe that is the safest way to make money and never go bankrupt.
Also, if you buy stock you can also sells calls/puts against your shares to protect you from a downside/flat days.
To reiterate, the statement above, is always easy to make, because this is the only way to make money. If you don't get into the market, then each year your money is running away from you, see inflation. Ally savings accounts just aren't as helpful.
Hopefully I have changed your mind and you will start looking into Vanguard funds at the minimum.