How much data do trunk coax cables carry? Please clarify some things about HFC network topography.

Pardon my ignorance on this, I am just trying to understand how a hybrid fiber-coax network works. I think I have most of the basics down, but I am unclear on how much bandwidth is pushed through the trunk cables before they split off and where the DOCSIS equipment is on the ISP side.

So if I'm understanding correctly, from the headend, you have fiber cables terminating into optical nodes where the data is converted to coax and then using RF amplifiers (these days just one?) it is branched off into smaller coax cables feeding about 150 subscribers per node these days.

Okay, but how many trunk cables initially come from the node? Are they physically larger/thicker than the cable that comes into your home? And the central conductor being then thicker allows it to carry more bandwidth? How many times are the trunks split off into smaller cables, i.e. how many steps?

When I think of bandwidth over a coax network, I think of the DOCSIS specs, e.g.1 gbps down, 200 mbps up theoretical using DOCSIS 3.0. But that is to the individual subscriber using the "standard" size coax that is found in homes. How is all of that data then encoded/congregated into the larger trunk cables, how much data can they carry, and where is the DOCSIS equipment on the ISP side? If it's in the node, then is there a DOCSIS modem for each subscriber in there or a larger DOCSIS "supermodem" that takes the larger amount of data from the trunk cable from a whole bunch of subscribers and demodulates it at the same time? If so, do these larger modems have different specs from the typical DOCSIS specs in that they can handle a lot more bandwidth? Where are those specs found?

Related to all of this, how much bandwidth do cable ISPs allocate to subscribers vs. how much is actually available? Theoretically, if everyone maxed out their connection at the same time to a node serving 150 subscribers, what % of their "promised" bandwidth would they get at that moment for a typical HFC deployment?

Okay, lots of questions, I'm clearly confused. I don't expect anyone to answer everything here, but any insight is appreciated.