Have you ever tried to haul everything to the gig on your back? The guitar, cables, costumes, merch, wireless system, FM3 etc ? Here in Ukraine that's how we do live gigs.
If you've tried this at least once - I'm sure you would be on my side.
Of course FM3 by itself is OK in weight. But it's never needed to take ONLY FM3 and nothing else!
I easily would pay twice the price of FM3 for twice the reduction of it's weight. It's 2024 - and we are busy carrying steel boxes with few PCBs inside which weight nothing...
There are other options to reduce weight for a loadout. I live in LA, and while I do drive to gigs, there are options to also take the subway/public transportation to gigs to beat traffic and not have to worry about parking. I also have traveled overseas and NYC taking public transpo to gigs and have my full rig with me. I fly all the time without checking anything and I have a full guitar + FM3 rig with me with plenty of room for clothes and toiletries.
Here's a couple suggestions.
1) Get a Ciari Guitar with the gig bag/backpack. It folds into a backpack size. You can even fit an FM3 into this backpack + the guitar if needed.
2) Ditch the Wireless system and get a Ernie Ball Headphone/Instrument cable. Your In ears plug into the FM3 and you take a feed from FOH. Less cables and gear to bring to the gig. If you absolutely need to go wireless guitar for a gig, get the Xvive system, or a Line6 G10 system which are the lightest and most compact.
3) Fm3 can go into a rolling Pelican Air (get the size of your choice). Use extra space to store whatever extra gear you need.
4) Get a mono flyby Ultra. This allows you to put the backpack on the trolley handle with a pass-thru on top of the rolling cart. If you have to take steps, wear the backpack in front of you. Easy to crouch, slide your front two arms into the backpack, and snap the rolling trolley handle back into the Pelican and you can walk up the steps. Store your costume and other needed accessories inside. The FM3 + other accessories can also fit inside this backpack if you don't want to get a pelican. The Ciari Guitar, folded can also fit into the Mono Ultra Flyby backpack (won't fit in a standard flyby).
There are plenty of options and this is why the FM3 is still the industry leader in the most amount of functionality per size.
I build and program kemper rigs for a lot of clients in addition to fractal rigs and there is a lot of missing functionality on the kemper player (2 pre effects, 2 post effects, no morph feature, no stereo out via XLR...which means you need a stereo DI unless you want to chance ground loop issues). It is missing a -lot-, and people are only enamored with the form factor. The morph feature is one of the biggest gripes/features that is missing that can make this a dealbreaker for kemper users.