I wouldn't consider it a mistake for newbies because even after buying without emergency funds set ups you can still set that up after having at least little to your portfolio while putting yourself to order, in my opinion some of this newbies that does this are opportunity grabbers which is even better than those who wait for the perfect timing which might not come, so I prefer they buy this bitcoin being imperfect and learn about things as time goes by than try to be all perfect set up all types of funds before ever getting to buy the real deal, bitcoin usually serve us opportunities like the little dips which a newbie could see and grab yet learn the who processes as time permits.
I think the summary of what I have understood so far is that the approach some newbies should really take is to emphasise the importance of taking healthy mindset actions and learning from others experiences and also learning to adapt to the market, rather than waiting for ideal conditions. The part you made mention of can still set up emergency funds after investing. I would say even if they don't have everything perfect from the start, in my own little understanding, they can still adjust, and then improvement takes place, plus improving their strategy changes over time.
Before you use fine English to confuse newbies, they need not complicate the Bitcoin investment process and should be able to work out a simple approach that will make it mechanical so that they do it with minimal effort and without much hassles. One of the test approach that is recommended for new investors is the DCA method which is the method of investing with lower amount of money on a regular interval like monthly or weekly. This method is great in that it allows the investor to buy with any amount they can afford and encourages them to make effort to sustain the investment process in a disciplined fashion.
However, it must be clearly stated that investment in Bitcoin must only be made from part of the discretionary income of the investor. The discretionary income, which is usually separated from the money for basic needs, should be properly allocated so that apart from the investment amount, emergency funds must also be kept in place to take care of unplanned things that can occur while the investment is in place. This measures will make even new investors to succeed in Bitcoin as thought they are pro in that area.