You can write your own sandbox profile if you're so inclined... but not easily, and you can't force it into a container in the Library folder, for example.
Except in this case, correlation is so strongly correlated with causation that it becomes causation.
Look, the plural of anecdotes is not data, but you can't argue against the general trend of "applications using web frameworks like Electron tend to consume more RAM" by saying "well in this specific case they made poor design decisions that would bite anyone in the ass"; while that may be true it misses the point, which is the much larger (and well-correlated) & overarching tendency of such apps to absolutely chew RAM.
That it's a "tired trope" doesn't make it untrue; it just means that enough people have accepted what is functionally the new state of the software application world that it's considered passé to call such things out.
Are you talking about the old problem of VMware and Hyper-V not playing well together, or suggesting that using both together solves Windows development woes?
KVM supports GPU passthrough, so, if you have two graphics cards, you can run Windows 10 with full GPU acceleration. Check out Passthrough Post for ideas/instructions.
The "new" (late 2020/TigerLake 11th Gen) 13" Dell XPS has a 16:10 screen, goes up to 16GB of RAM (I surely wish it went to 32, but ¯\_(ツ)_/¯), great SSDs, can be configured to i7, and is officially supported to run Ubuntu.
Lenovo is also shipping laptops pre-installed with Fedora, if your tastes run to RPM instead of DEB Linux. And of course, both will run Windows + WSL 2 just fine.
I will say, however, that the post-butterfly key 13" and 16" MacBook Pros have great keyboards and work really well.
TreeStyleTabs in Firefox (which is a great tool regardless of bookmarking), keeps track of parent/child relationships, you can drag & drop into subsets to create the relationship you're talking about, and has a "Bookmark this tree" feature, which would create a folder with subfolders with the top level named as you choose.
(I use the heck out of this, both for the extra vertical space that comes from hiding the top tab bar, and for the conceptual organization that it provides).
Privacy/no-cookie sharing: Container Tabs + Multi Account Containers in Firefox is incredible. Yes, I realize those are extensions - but that kind of control or extensibility isn't even possible in Safari.
Which is actually the biggest reason I don't use Safari, it has no support for profiles or user-chosen cookie separation (multiple different accounts for GSuite, etc).
As for Chrome just getting patched with zero-days - fine, but remember that Safari doesn't have the concept or ability to do Site Isolation the way Chrome or FF do, Chrome uses the macOS sandbox the same way Safari does, and there have been plenty of Safari CVEs as well. Chrome is usually the last to fall at Pwn2Own; pointing out "oh they just patched a zero-day CVE" doesn't mean much, especially since Apple pushes Safari updates far less often than Chrome does, and will often leave desktop Safari unpatched for weeks after iOS has been fixed.
Tracking the changes to the Signal Desktop Application on the WhisperSystems github, it looks like they're moving to an Electron app (like Slack). Thumbs down from me for code bloat, but it'll be nice to have a separate app and not be required to keep Chrome open all the time.
Video calling on Signal works a little differently than WhatsApp to my understanding; it's decentralized and so the quality is lower, but the Signal server manages to keep from collecting any data, and backdoors can't be added (it just sets up the call and then bows out).