It’s funny the ancient romans used to call English people, “Barbarians incapable of civilisation” only for them to inherit the glory of Rome. And turn central London into the most dense place for their classical architecture all the while demonising the same people that founded the city

it used to be called londinium ffs
The West never inherited "the glory of Rome." This notion of continuity is a-historic fiction. Rome effectively colonized and taxed Germanics and other peoples found in Central Europe, introducing an extractionary infrastructure and control-based apparatus for the gain of Rome's central.
After the Western Roman Empire collapsed, all the hallmarks of Roman presence in Western Europe went out with it, with all the regions returning to completely local rule, reverting to their old ways, eliminating the taxation systems, architecture left behind, etc.
They try to associate the Catholic Church with Rome, but the Catholic Church was not Rome; it used certain Roman-sourced functions for administrative processes, but the domain of Central Europe was basically medieval chiefdoms, with this theologically based church being a fragmented religious-based order that used Roman symbolism to hold pseudo-power while pretending they never wanted it. In practice, their elusive games that had a real impact on the medieval regions were extremely distinct from Rome.
We have fraudsters linking this so-called continuity by pointing at the Catholic Church, that were of Roman origin, emphasizing aspects like how the religious body used Latin as a liturgical mode -- all that is nonsensical because Rome was an empire, the catholic church was a religious organ that only claimed to have Roman continuity for the value judgment of legitimization on the collective feudalistic notions of medieval Europeans totally detached of such reality.
The catholic Church has more impact on Western civilization than Rome. That is the irony. Christianity during the post-Roman world set various conditions that incentivized globalization, making rulers under the Church form greater regional connectivity. There is a reason why aristocrats, royals, and dukes had mixed backgrounds, since they had more in common with elites of other kingdoms than their poor citizens.
It was during the Early Modern Era were these "enlightenment" concepts appeared, where these Europeans started to draw ideas together that indeed shape today's secular nations to a high extent. The irony was, these "enlightenment thinkers" used the Greek and Roman civilizations to draw upon an imagined ambitious projection, as a way to craft a trajectory away from the entrenched medieval religious and feudal bodies. It is also worth noting that Europe was highly structured already in the macro-sense by the time these secularists were crafting the newer stage for a separate collective ideal-based thinking, which in reality was a mixture of diverse thinking but more defined by its time than the past, and also entirely discontinuous from the Greco-Roman conception of continuous inheritance.
If one knows philosophy, European thinkers such as Hume and Kant shaped European thinking more so in the critiques and discourse of Greek thinking than in adopting Hellenic philosophy. At best, these Westerners point to this discourse and say, "That is a Greek inheritance," which is performative and utterly irrelevant because it is merely aesthetics, costuming. Sort of posturing without substance, and surely has no legs to stand on in this conversation.
And secondly, man, the architecture of European cities was inspired by the past, but they also had their own innovation. Rome or Greece never looked like Vienna. All houses today have a myriad of influences that escape the average person outside the field of architecture. But you can ask any person within that discipline, and they will tell you that what makes the typical suburban house is the culmination of many diverse housing designs. Europe had many stages of architecture that used Rome and Greece as inspiration, but it had innovative epochs; the same can be said for art in general. It was more of an inspiration than a sign of continuity.
London was not a large hub until the 16th-17th century. That is when you see the London you know of today appear. The architecture you see today was defined by these artistic epochs of Early Modern Europeans that had cultivated an innovative charge rather than claiming Roman or Greek heritage or a false revival (although I would not put it past these pretenious artists to think they revived things because they were pompous people).