If you’re a hobbyist researcher, or you work for a small firm, it is a great value for that line of work. True AI-oriented cards retail for a much higher cost, and the 4090 is far less expensive than if you were dealing with an NVIDIA A100.
Further, AI is a relatively young market sector, so if you’re not looking to break the bank it makes sense to invest in something more cost-effective.
Time will likely make the overall investment necessary to get into AI less expensive. Right now, if you aren’t a massive firm working with an automotive manufacturer, it stands to reason to invest wisely in your equipment.