Neither Jackson or Watkins are good options, it's better for Manchester United to wait for the next transfer window in order to get better striker. The task of Manchester United in this season is to survive and not relegated to Championship.
Jackson is the worst possible option they can go with if they rush. I see that they want to get everything and be done, but if they end up with Jackson they would be horrible. I see that Cunha and Mbuemo was their only transfers so far, at least only two that I have seen mean anything, not sure anything else. But if we focus on the reality, that wasn't enough at all and they overpaid for the players.
We need to consider things changing a lot worse and they need to get more players. However, just because they "need" to, doesn't mean they should rush, because if they rush then they won't get any good return on their investment. Look at how Cunha was last game, he didn't even look like he worths that much money they paid for him.
Nicholas Jackson is not a flop he has scored 14 goals in Premier league 2023-2024 season and added another 10 goals in the 2023-2025 season for Chelsea. Adding up to 24 goals only in 65 games, it's sort of stunning for his age and circumstances. His conversion rate with 25+ shots ranked top of the league at around 25% last season, even though he missed a couple of big chances.
At the meantime Ollie Watkins who is at Aston villa is off the radar for now, United submitted a deal that is valued up to £60M, but Aston Villa declined. In Unai Emery's eyes, he is valued at more than £60M. Watkines has 17 goals and 14 assists in the 2023-2024 season and has gained stability and experience in EPL.
So, Jackson is not A washout as the media criticizes, his change is legit. But you can say that Watkins is a better choice with better experiences, and because of high demand, if United can't get him, they need to go for Jackson or look for strikers in the market.