You're missing the point. This is about quality of life, not pure value for money. No, a laptop isn't always better, but it sure is a lot more flexible.
In that case a PC is of course better, but the reason is mostly because it functions as a server and a laptop would be unnecessary, not because a laptop isnt flexible enough (which was OPs advantage of a laptop...
I personally have my laptop (with dGPU) connected to a 16 port USB hub when plugged in (and an ultrawide monitor), connected to all sorts of things (backup HDDs, microphone, audio system, camera etc). And when Im on the go, chances are I can do without those things for that time... Different things work different people though.
I can see the logic there, but why not vote based on relevance rather than agreement? That way comments that are on-topic and further the conversation rise to the top, regardless of whether they align with the Lemmy hive-mind. Some of the best threads are the long ones with a spirited back and forth between ideological opposites, and those would go away (or be pushed to the bottom) if both sides simply down-voted each other back to net-zero.
As a weird byproduct, we also get fun stuff like Hanlon's Law, which states that the fastest way to find the correct answer to something online is to confidently state the wrong one on Reddit/Lemmy and wait for your comment and the actual answer to float to the top. After all, people love to correct one another, and we often come to Lemmy to learn about other points of view and have our own views challenged. As long as everyone is debating in good faith and trying to add value to the conversation (which should be enforced by downvote), differing opinions are a good thing.