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.
I think any newbie should be more interested in regular purchase of Bitcoin with available discretionary income rather than trying to adapt to the market sentiment. This is because trying to adapt to the markets might introduce some distractions and gambling mentality in him and he sets out to accumulate only when he terms it favorable for him to buy.
That being said, an newbie investor should avoid distractions and noise from the markets and focus on following up his regular buys with much commitment and dedication, mastering his cashflow management practices and building out his backup funds as he progresses with his accumulation journey.