This is the kind of historical overview stuff I'm usually fairly interested in, but the questions posed seem like missing the forest for the trees, or else a convoluted and roundabout route to the obvious conclusion.

People take way too much of a deterministic approach to history and try to view things in terms of trends and forces, when it's really about people making choices. A lot of times those choices in the aggregate resemble a trend or something like that, but there is still a collective will making a choice for a reason.

See, right there. The general determining factors are that people who spoke languages died or found it easier to speak other languages. I.e. the literal lingua franca, which made it easier to do business and achieve one's ends, as is also the case with English nowadays.

Racism. Indians have the same racial roots as the English, who were also a lot more invested in India than the Dutch were in Indonesia. The former also had a more definitive and distinct national identity. It's hard to impose something like that on someone else, when you're not too sure how it goes yourself. The Dutch only really distinguished themselves from other Netherlanders politically a very short time before colonizing Indonesia. Also, I'm not sure what the situation was in pre-colonial Indonesia, but given how India goes, the lingua franca explanation is glaringly obvious for the Indians themselves, as well as the external advantages. It's not like you could find a Dutch-speaking colony or outpost in every timezone on the planet. An Indian who learned English would find that useful in Canada, Australia, Ireland, Middle Earth, the United States, various places in the Caribbean and Africa and even for getting along with his similarly educated neighbors from other parts of India, which is no more linguistically homogeneous than Europe. What similar incentive is there for an Indonesian to learn Dutch?

Again, it comes down to reasons for people to do a thing, rather than any inherent property of the language itself. I don't know if the book is overlooking that point, or arrives at that conclusion, but if the latter, it would seem a weird question to try to answer with a whole book. It's like that Leigh Butler twit going on a whole rant that she can't find an explanation quickly on the internet for the practice of referring to ships as female - it's so blindly obvious to anyone who gets it, no one bothers to write it down. Hence the validity of the author's claim to be the only one doing such a study. Just because Tolkien's world existed to explain his linguistic inventions doesn't mean the real world follows that order of cause & effect.

I'd be perversely interested to see how. If he has a better explanation than merely pointing out chronological or numerical similarities between the colonization of two different lands.
Glorious maybe from a linguistic perspective or some sort of academic or aesthetic mentality, but in no way otherwise. A handful of Spaniards didn't take down the Aztecs because of the inherent superiority of the European race, they had a fuckton of people who had had it up to here with their Aztec neighbors on their side.

I would hazard a guess that no one found Paraguay sufficiently important to exert the sort of control imposed in Mexico or Brazil, or the Guarani sufficiently troublesome to put down and suppress, or the place inviting enough to move into and outbreed the natives. Human choices.

Maybe because Hebrew speakers didn't stick up enough to get hammered down by the Romans. As you note, it was resurrected later on (it did not resurrect itself). There were probably more Hebrew speakers who carried it abroad in the diaspora than there were Aramaic speakers. Then, too, if any Aramaic or Phoenician speakers survived the infamously thorough Roman devastation of major cities in their regions, they subsequently fell under the dominion of Islam, with its Arabic lingua franca, while the culture that supported the few Hebrew speakers was spreading through Europe and west Asia.

It sounds kind of neat for the latter stuff, because of the utility of linguistic data as an indicator of more important phenomena. For example, as an indicator of a lot of the interwar ethnic issues in Eastern & Central Europe, it is useful to see how far back German was displaced by Slavic languages as the medium of intercourse in most central European cities. In many cases, it was surprisingly recent. Looking at lines on a map will not give much indication of the cultural influence of the German people throughout Europe, as politically, German didn't seem to matter much until the 19th century. But while ethnography or geography might note the existence of countries like Bohemia and Romania and Poland, as well as their Slavic populations, it doesn't show how much official business, trade, research & science and education was conducted in German throughout the Middle Ages and beyond. Most of the German street signs didn't come down until the 19th century. Is that due to some property of the German language, or was it because of the human capital contributed to those countries by people who happened to speak German. People who were originally geogrpahically close to the origins or Western advances in culture, science and societal development, but who lacked the political unity to bind them to their country of origin, and allowed them to move out into cultural frontiers in search of prosperity or peace. Language is a symptom, not a thing unto itself.

I'd recommend "Conquest And Culture" by Thomas Sowell for a look at those sort of factors and how they influence culture, and in turn, language, which is both a symptom and a mechanism of transmission.