Another commenter already identified the meat of the problem; you were restricted access to computers, whereas your children are not. Here is an article about that exact conundrum, on the concept of "antagonistic learning":
https://medium.com/@ThingMaker/educ-103-antagonistic-learnin...If you DM me, I will be happy to send you a list of similar essays that explore the concept of learning and teaching and why it's done poorly these days. I suggest you start with the essays and writing of John Taylor Gatto; his writings were ludicrously inspirational to me. Here is the first article I ever read that made me realize that I was a deficient learner and had never truly engaged in learning: https://www.cantrip.org/gatto.html
Consider that Roblox and Youtube are essentially slot machines for dopamine. If you want to engage with your children as creative, disciplined learning machines, they must be weaned off of addictive superstimulus-coded platforms, which is damn near impossible given the tech demands of modern school. I don't have any advice for you on that front, except that the more time you can spend with them the better. Perhaps you can start by playing Roblox and watching YouTube videos with them (taking care to only offer them positive and genuinely interested feedback on what they choose to do), and after they've built you into their habits, begin steering them towards more productive activities.