The first disciple to attain Stream-winning was Kondaññā the wise,
Aññakondañña. When the bodhisatta was born, Kondañña was one of several astrologers who was invited to the palace to examine the new-born infant. Although the youngest of the astrologers, he was the most skilled in his craft, and was the only one to predict that the bodhisatta would definitely become a Buddha.
So confident was he, that he renounced household life and became a recluse in preparation for the time when Siddhattha would gain Enlightenment. Thirty-five years later, while listening to the Dhammacakkappavattana Sutta, Kondañña was the only one of the five to immediately attain Stream-entry — the other four ascetics had to practise Satipatthāna meditation for successively longer periods of a few days.
So, thirty-five years of continuous meditation should not be regarded as too long to attain nibbāna. After all, we have wandered in samsāra for an infinite length of time to get to whatever stage we are at now. If the preparation has been thorough, then Arahantship can arise in a millisecond as happened with Bahiya. If the preparation has not been enough, then no amount of wishing or hoping will lead even to a glimmer of insight.
If anyone has obstructive kamma then attainment may be impossible at the moment, so do be very careful not to discourage people from practising meditation intensively, or disparaging them for not facing up to "real life" etc.
Meditation is easy — it is not meditating that makes life difficult. If you do get the opportunity to do a long retreat for two months or six months or a year, go for it. If you don't, then try to attend a 10-day course at least once a year, and a one-day retreat at least once a month.
To return to the thread's topic. I assume that most Stream-winners will be reborn in the celestial realms and may not return to the human realm again until the time of Buddha Maitreyya — most of the stories we read in the texts talk of faithful disciples being reborn in the deva or brahma realms. There are none that I can recall at the moment mentioning rebirth in the human realm again. Even in the lowest Cātumahārājika deva realm one celestial day is 500 years in human terms, so for them the Buddha's Enlightenment happened only last week.
If a Stream-winner was reborn in this current Buddhasāsana, they would have perfect moral conduct throughout their life. They would be able to attain to the nibbānic stage of phalañāṇa at will, for short or long periods depending on their concentration and determination. It seems unlikely that they would neither be born into a Buddhist family, nor gravitate to a Buddhist country, but it is conceivable that they would not recognise the nibbānic stage for what it was as that is just a matter of theoretical knowledge.
There are
extraordinary people in this world with skills that are far beyond our abilities. For them, it is not especially difficult to do what they do. For me, 3.142 is about as far as I can remember the value of pi.