“AGI is not likely” is not a good answer. If you assume that it’s not possible but you’re wrong, you miss out. The risk, as you say, is too high. The opportunity cost of ignoring the risk is subsequently high. Therefore the only logical course of action is to proceed as though AGI is possible and to do it right.
If AGI is not possible, we will still solve many problems along the way. If it is possible, then we’re more likely to do it right.