Only positive aspect of the laptop is it's portability. In all other aspects, desktop PC does better.
Also, with laptops, you'll be running that thing on thermal threshold, since laptops are poor cooling wise. Also, your RTX 3060 inside the laptop, isn't equal to RTX 3060 in a desktop. It is instead equal to desktop RTX 2060,
So, unless you need laptop for it's portability reasons, there are no other reasons why to buy a laptop.
If it would be desktop, whereby you are free to upgrade components (namely GPU, to keep up with latest games), then 5-6 years would be even possible. But with a laptop, where you can't upgrade anything - not so much.
For example, if we were to look a 6-7 year old GPU, e.g GTX 1060 (came out in Q3 2016) <- would this GPU still be somewhat relevant today? In terms of gaming and rendering? I don't think so.
I had GTX 1060, that i bought in 2016, but i replaced mine with GTX 1660 Ti in 2020. (I have desktop PC.) So, got ~4 years out of it and i'm not that picky either, instead, i'm just casual gamer.
With this, i think you should get ~2 years out of your laptop. Less if you're picky and more if you're willing to put up with lower in-game graphics quality in later years.
Btw, for rendering, proper 3D rendering, minimum RAM amount would be 32 GB, while 64 GB is preferred.