Angle braces like that are definitely not necessary. Mine is rock solid and just has the regular shape.

I love my standing/sitting desk. I use an uplift from thehumansolution. I've been using it for about 8 years now. I bought one of their frames only and removed the desktop from my old desk to mount on top. I'm not sure if they sell just the base anymore, but I see they have a lot of options. I also use a lifespan brand walking treadmill under mine that I've been using just as long. I highly recommend both. It has done wonders for my back issues that kept getting worse after prolonged sitting.

It is not wobbly, and I have my entire desktop and triple monitors with heavyduty tri-monitor base on top of it.

https://www.thehumansolution.com/uplift-adjustable-height-standing-desk

I did task rabbit for a while a few years back and put together a fair number of IKEA ones. They aren’t the cheapest but damned if they aren’t solid af.

I've had zero issues with my desk from monoprice: https://www.monoprice.com/product?p_id=42763

I don't normally do this, but I had such a good experience with them that I wanted to sing their praises.

I ended up getting a custom one by Deskhaus and I love it. It's made in the USA and the guy who runs the company is really upfront with a lot of details behind the desk and their competitors. Their youtube channel helps answer a lot of questions about their various desks.

iMovR isthe brand I went with. I got a l shape with a really nice wood top

Please reword your post title to be a question.

I've got a flexispot E7 and I'm really happy with it. It's quite stable but certainly not the most stable solution. But there's also the E7Q which has 4 legs instead of only 2 which should increase the stability but I haven't tried that one.

Australian-centric (I think) but my Desky one is great

I have an Uplift desk and it's pretty solid despite being on wheels. It's entirely possible that we have different standards of wobbliness but you might want to consider Uplift. They have a lot of different sizes, finishes, and accessories available.

Follow up. I looked at everybody's suggestions, not all of them were available in my country. But IKEA was. I pulled the trigger on the IKEA desk in the title. And it's super stable. Doesn't rock at all. Very happy. Thank you all for the input

I got an iMovr Freedom base with a butchers block.

Weighs probably 100lbs, costs around 700-800, and as solid as can be.

We have this one. FEZIBO Dual Motor Height Adjustable Standing Desk Frame, Adjustable Desk Legs for 48 Inches to 63 Inches Desk Tops, Home Office Sit Stand Desk Base, Black (Frame Only) https://a.co/d/3WsKBHo

Wobble often comes from the floor being out of level as opposed to the desk itself. As long as the desk has adjustable feet you shouldn't have any wobble.