32GB won't fix slow preview generation.

Probably not. Preview generation in Lightroom is mostly CPU and disk I/O bound, not RAM bound. If you’re already at 16GB and not hitting memory limits, bumping to 32GB won’t make previews render faster.

Where 32GB does help is when you’re juggling a huge catalog while using other apps (like Photoshop or a browser with fifty tabs). If you keep running out of memory and Lightroom starts swapping to disk, that slowdown will affect everything, including preview generation. But the task of generating previews itself is crunching pixels, not keeping images in memory.

So unless you’re constantly hitting 90%+ memory usage, save your money. Get a faster CPU or an NVMe drive if previews are too slow. Or just generate smaller previews.

Future You might appreciate 32GB for multitasking, but it’s not a magic bullet for Lightroom’s preview engine.