Even with minimal returns, 401ks are great tax shelters. 25% with every contribution. I always maxed out my 401k, IRA and HSA for that reason. Could keep about 30k a year away from the tax man. Over the years I switched between stable asset and some stock funds. Eventually, I did an annual in-service rollover out of the 401k into a rollover IRA at a mutual fund b/c I didn't like the 401k choices. My plan allowed that. Got out of the market before the crash, luckily, with very nice profits.
A 401k is a great tool which my former employer did not initiate until the mid-80s. I jumped in happily. Their match was a paltry 25% of 4%, or 1% of one's income. They also had a DC plan to which they contributed 5% of one's salary beginning in 1994. So, I guess their overall retirement contribution was 6% of salary. Not overly generous by any means, but it is what it is.
The tax-shelter aspect, for me, was critical.