Upgrading a entry level hybrid bike or purchasing a new better one I currently own a Trek Dual Sport 3 2020. I'm very happy about the versatility of the bike from a riding point of view, but also &quot;accessorization&quot;. I'm mostly doing light trails (no jumps, but roots and loose stones) and road. I'm also planning a 800km tour — road and gravel.
But I'm not so much happy about the components. I have the impression that I'm using a bit harder that what the bike has been designed for, and would like to either upgrade it or buy a new one.
I've read many comments saying that upgrading an entry level bike is a money hole and money is better spend buying a new one, and I agree if speaking about well-defined categories or old bikes. It seems less categoric here, the options I see are:

upgrade it to better components;
buy a new bike from a similar category, but from brands that have better value for money (like Cube Nature or Giant Roam), and either resell the Trek or keep it for guests;
buy a new gravel/cross-country MTB: my main reserve is in fact that I would loose versatility: a gravel would be less capable off-road, and a cross-country less capable on-road (I'm sometimes doing the 2 in a single trip).

I have a couple of questions:
Option 1:

is &quot;worth&quot; spending the value of the bike in wheels and drive-train? (thinking about Mavic Allroad (S) wheels, SRAM Eagle NX/Apex drivetrain). The total cost - including the bike - would be a bit more than the highest spec'ed Dual Sport for slightly better components. My interrogation with this approach is about the suitability of the frame: if I have sturdier components and I keep using hard, there will be more fatigue for the frame.

Option 3:

is my assumption that I'll loose versatility correct? For gravels, I would think so because of the lack of suspension and the dropped handlebar. And for X-country, if I fit thinner tires and a 42T crankset, it would be possible to have a similar specs, but I noticed that for example Trek specifies that 32T cranksets are the max for their X-calibers, so it wouldn't be possible to install such cranksets. I haven't seen similar restrictions with other brands, but only a few are selling frames separately.
Upgrading an existing bike piecemeal is always going to be more expensive than buying a new bike with the specs you want, because manufacturers get components at a discount.
Regarding Option 1, upgraded components will not transmit more stress to the frame, if that's what you're asking. It is possible (but seems unlikely) that the frame was engineered with just enough safety margin to allow for light trail riding, but not more intense off-road riding. I wouldn't let that guide my decision.
The gravel-bike category is a broad one, and some bikes are more road-ish, others are more MTB-ish.
If you frequently cover both tarmac and dirt in a single ride, that sounds like a good argument for a gravel bike. Everything is a compromise, and you need to figure out what compromise you're most comfortable with.