Is the new craze to invest in non-fungible tokens (NFTs) a fad or a good short-term or long-term investment for people to consider?

Here the devil is in the details. There are a few that have some value. There are many that do not. There are many masquerading as useful applications of blockchain technology that are more a gimmick than a solid contribution that has likelihood of a significant lifespan that would justify a corresponding fee that might appreciate over time and constitute a reasonable investment. So this is something that would need to be explored case by case. There will be many false starts, many dead-ends, so there will need to be careful scrutiny to separate the wheat from the chaff.