I was trying to make the point that investing in a Roth IRA has no penalty for principal removal vs a traditional IRA. That's the no risk part. Investments within the Roth are of course at risk.Vanguard's crystal ball is no better than anybody else's. There is always some expert claiming the maret will rally while another claims it will crash. Nobody knows with any certainty what the market will do which is why we can only do our best based on past statistics. I'm sure you've all heard the story that the best performing accounts are those owned by dead people.
All to say, time in the market beats timing the market.
The roth investment vehicle has nothing at all to do with risk. You can invest in almost anything with a roth and you can lose it all, including your original investment amount.
Further i was also making the point that it's historically Much better for young investors to invest in stocks vs Bonds over the long term and one of the first places to put your long term investments would be a Roth which has good tax advantages as well.