This, exactly. The only "flaw" of Vanguard's admiral funds is the $3000 minimum. For many of my friends, that is a bit of a high hill to climb to get started. Then again, those same friends seem to think nothing about speculating on whatever the hipster cryptocurrency is, so perhaps they have a different set of issues they need to address.
The target date funds have a $1000 minimum and are quite reasonable options for retirement or general diversified investments. The expense ratio is slightly higher, but if you have less than $3000, the difference is miniscule.
Or you can buy ETF versions of Vanguard funds. Same expenses as mutual fund versions, but the minimum purchase is 1 share. Free to trade from a Vanguard account (or something like this Schwab account, since its exchange traded).
Your friends can start off buying Investor Shares in the fund(s) they like. Once they hit the Admiral Shares minimum, they can convert over to them[0].
Many of their funds also have corresponding ETFs, and I've found that most (all) have similar or lower expense ratios, and the minimum buy is a single share (of course, you can't buy fractional shares like you can with mutual funds, so that can be annoying).
Vanguard has gotten rid of a lot of their investor-share classes of mutual funds. VTSAX used to have a $10k minimum. Now it has a $3k minimum, which used to be the amount to get the equivalent investor shares fund.
$3000 is definitely a hill, but wouldn't they need to at least climb that hill to put away a safety buffer /before/ putting any post-tax money into equities??