Кстати о важном, т.е. о бабках. Простой поиск дает:

TRAIN:

• There are two sources that estimate the cost of training GPT-3 at $12 million and $4.6 million.
• Training GPT-3 would cost about $4.6M on a tesla v100 cloud instance.
• It cost $50 million to train Chat GPT.21 Jan 2023
• time it takes to train a ChatGPT model can range from days to several months, depending on the size and complexity of the model, the quality and size of the training data, and the available computational resources.
• GPT-3 model has 175 billion parameters and reportedly took several months to train using a large-scale computing cluster with thousands of graphics processing units (GPUs)

RUN:

• You would need 5 80Gb A100 GPUs just to load the model and text. ChatGPT cranks out about 15-20 words per second
  
• the cost of running ChatGPT is $100,000 per day.

Ну в общем, очевидно, что для простых бизнес моделей типа 19$ в месяц с одного говнокодера или фейсбушника это никогда не окупится. Это игра по крупному для взрослых.