What exactly is the judgement of Rosh Hashanah?

Question

In the Rosh Hashanah Musaf, it is implied that all human beings and countries are judged on this day whether they will have peace or war, life or death, and in the Unesaneh Tokef prayer, this is extended to many other forms of prosperity or suffering. It is also implied many places in the Gemara and Mishnah that the righteous are decreed for life and the wicked for death, for example:

אמר רבי כרוספדאי אמר רבי יוחנן: שלשה ספרים נפתחין בראש השנה, אחד של רשעים גמורין, ואחד של צדיקים גמורין, ואחד של בינוניים. צדיקים גמורין – נכתבין ונחתמין לאלתר לחיים, רשעים גמורין – נכתבין ונחתמין לאלתר למיתה, בינוניים - תלוויין ועומדין מראש השנה ועד יום הכפורים. זכו – נכתבין לחיים, לא זכו – נכתבין למיתה.

Three books are opened on Rosh Hashanah: one for the totally wicked, one for the totally righteous, and one for the intermediate. The totally righteous are inscribed and sealed immediately for life. The totally wicked are inscribed and sealed immediately for death. And the intermediate people are left dependent from Rosh Hashanah to Yom Kippur. If they merit they will be inscribed for life. And if they do not merit, they will be inscribed for death". (Rosh Hashanah 16b)

How can this be so?

• Weren't there many obviously wicked people or regimes that survived through more than one Rosh Hashanah (like the Egyptians who enslaved Yisrael, the Nazi regime, etc.)?
• Furthermore, how could it be that prosperity is determined on Rosh Hashanah but the rain, grain produce, and fruits are judged on the three holidays (Rosh Hashanah 16a)?

Answer 1

There are at least 5 approaches that address the first question:

1) The 'life' and 'death' in question are not that of this world, but of the next (Tosfos among others).

2) 'צדיק' and 'רשע' in this context don't mean 'righteous' and 'wicked', but rather 'exonerated' and 'condemned' (as in Devarim 25:1). (Rabbeinu Nissim, Rashba's first approach, Tosfos Rid, Mordechai, Ramban)

3) "רשעים גמורין" means absolutely 100% wicked (Sefer Hachinuch, Pnei Yehoshua). Very few people fall into this category, and it's impossible to know with certainty if any particular individual does, even if they have committed the most heinous crimes.

4) "מיתה" means a shortening of one's life from the length that had previously been decreed (Raavad, Rif).

5) "מיתה" means that one loses the hashgacha/special attention/protection of God and he/she becomes vulnerable to nature like an animal (Shu"t Halachos Ketanos).