A big part of it is the fact that Meta tries very hard to not lose the relevance against OpenAI, so they keep building and releasing a lot of their models for f

A big part of it is the fact that Meta tries very hard to not lose the relevance against OpenAI, so they keep building and releasing a lot of their models for free. I would imagine they're taking huge losses on these but it's a price they seem to be willing to pay for being late to the party. The same applies (to smaller extent) to Google, and more recently to Alibaba. A lot of free (not open-source, mind you) LLMs are either from Meta or built by other smaller outfits by tweaking Meta's LLMs (there are exceptions, like Mistral). One thing to keep in mind is that while training a model requires A LOT of data, manual intervention, hardware, power, and time, using these LLMs (inference, or forward pass in the neural network) is really not. Right now it typically requires NVidia GPU with lots of VRAM but I have no doubt in just a few months/maybe a year someone will find much easier way to do that without sacrificing the speed.