A language can die in a number of ways.

One way languages die is that they don't actually die but what we refer to as that language was actually just something from a single point in time which has now passed long enough ago that everything derived from it feels considerably different. In the case of Latin, it didn't actually die off. It just became something else. All currently used languages are constantly changing. English changes with every generation as does every other language, and things like distance or geographic barriers make those changes happen in some areas but not others. That's why English in Australia is different from English in the United States. Latin had a more formal standard, and then as a language of empire had a bunch of variations that were spoken in places like what is now France or Spain or Romania.

Over time, those diverged even more from what we might otherwise think of as Latin, and what they spoke in Rome also was undergoing significant changes. That's what got us where we are today with the Romance languages. But you can make the argument that French isn't just derived from Latin but that it actually is Latin.

Another way they die is they get replaced. So there was this language called Ahom spoken in North East India. It was a Tai (Thai) language that had a powerful kingdom behind it. It left a lasting impression on the region and the other languages of the region. It had a rich written tradition, its own alphabet, and even the name of the state of Assam from which you might recognise as a place where tea comes from is named for the Ahom ("Assam" in Assamese is /ɔxɔm/, i.e. Ahom). Now, in Assam, the dominant language is not a Tai language but rather an Indo-Aryan language called Assamese which is closely related to Bengali. Not a single soul alive today speaks Ahom (although revival efforts are underway).

Why then? Because as more people started moving in to the region, language usage switched, and as the Ahom political entity came under British control in 1838, and things like oil and coal were uncovered and mined there and labourers from India were brought in, the language eventually fell out of use so severely that it is today only preserved in palm-leaf manuscripts in private homes.

Ahom speakers were already a small minority within the region, as the North East has always been a place that people from all over the greater area converged. As this continued, their influence waned, and their language didn't manage to maintain regular usage. Hence the death of Ahom.

So what about English then? Given these two routes, we could imagine either of them happening to English. One possibility is in a few hundred years we consider American and Australian and British to be different languages. This is not far fetched; Dutch and German German and Swiss German aren't all that far apart in the grand scheme of things, but we consider Dutch as distinct. So maybe we consider English a dead language, or we consider English to only refer to what's spoken in England and Australian (I propose "Strine" gets carried over as the name if this is to happen) is a different language.

Alternatively, idk China takes over or something, and within a couple generations English stops being seen as all that useful. This happens a lot: Some influential language goes from being a second language to being preferred over the heritage language. This is happening in China today where languages like Wu (incl. Shanghainese) aren't being taught to kids who would have otherwise been native speakers, in favour of Mandarin.

But there's a third option. Maybe we don't just abandon English for Mandarin. Maybe Mandarin has a major influence but English as we know it just starts changing to be more Mandarin-like. This is what happened after 1066 when English became more Norman. Of course we still call it English, but there's no real reason that had to happen. Old English is incredibly foreign to Modern English speakers. That they both get called English is just a convention, and doesn't actually reflect anything beyond that.

So those are the ways English could "die", and how many languages in the past have died. It doesn't need to take having only a dozen elderly speakers of an already small language for it to die off. All it has to take is a shift in preference or a shift in usage such that future generations deem it as a difference of kind rather than degree.

Also for what it's worth I think 200 years is too short for a natural drift to cause us to call it something else, but not too short to just be wiped out. 200 years ago English would still be readily understandable. Probably in 200 years they'll still be thinking it's the same core thing it is today, just changed.