On the Ethereum EVM it is 12,000,000 ether gwei. Most blocks are full. If you are willing to pay 12,000,000 ether gwei at competitive gas prices, it will get mined.
For an image application you can probably use as many blocks as you want to create and store a larger image.
As blocks are already full, this wont change anything, some people will get priced out for the time being or they pay higher gas price, miners get paid 12,000,000 ether gwei * gas price either way.
So gas prices right now are like 135 gwei.
12,000,000 ether gwei is 0.012 ether. 0.012 * 135 = 1.62 ether @ $1,704 per ether = $2760 cost if you want to fill up an entire block
Binance Smart Chain EVM has 30,000,000 binance gwei gas limit. And the binance token is much cheaper to begin with at the moment.
and there are other EVMs, you can find the EVM you want to use. Ethereum mainnet EVM has the highest number of nodes to store it though.
Its economical if you can sell it for a higher price. No different from any other art trade, artist can take the risk or a studio can front capital.