The Linux kernel devs have banned VLAs from their codebase, so you can get a lot of context from that discussion. (https://www.phoronix.com/scan.php?page=news_item&px=Linux-Ki...). One of the drawbacks of VLAs is that, maybe just because of an unfortunate choice of syntax, it's surprisingly easy to create one accidentally: https://lwn.net/Articles/749064/