The second prediction, for a recession in 2019, turned out to be wrong. But unlike impeachment, which would never happen or be successful, this one continues to evolve, into 2020 and beyond. It mostly deals with the trade war with China (and other countries), which is still ongoing. Whether and when it will stop is far from certain. Worldwide economies are clearly treading down, just how much and how fast depends on Trump policies or, more precisely, whims. Prediction is that 2020 will not be better than 2019.
Turning direction, the year 2020 might finally see the end of tennis domination by Federer, Nadal, and Djokovic. They will not be completely gone, but chances are new GS winner(s) will be crowned in 2020. It is amazing that Nadal and Djokovic got all 4 GS in 2019, with Federer coming so the closest with one. This is in contrast to the sports of badminton and even table tennis. Why? Not many plausible explanations have been given, especially considering this phenomenon is unprecedented. One can argue that athletes take care of their bodies better than before, but this alone can't explain why only tennis. Or Federer, Nadal, and Djokovic are geniuses. But historically there have been geniuses in other sports as well, but they didn't dominate well after turning 30. For example, Lin Dan, the greatest badminton player ever: the last tournament he played that truly demonstrated his world champion level was Asian Games 2014, when he was 31. After that, his career has been completely different. Or Ma Long, who has the most possible table tennis titles than anybody else in history. Now just a bit over 30, he is already up and down, clearly not the player a few years back.
A probable reason is that tennis is unique in terms of how it is played. The most distinctive feature is that you can get easy points by serving, which greatly conserves energy. Federer and Djokovic all have good serves. Nadal doesn't serve fast, but he is left-handed, and balls spin. If you compare them now and 5-10 years ago, you will see Federer relies on his serves more and more: in fact, his service speed is the only one parameter that remains as good. You can count Serena Williams in as well. Federer seems to improve on his backhand, but this is a mirage: he no longer runs much for his forehand, so he stays on his backhand side more, which gives him more preparation for backhand. Djokovic doesn't run around the court as usual, neither does Nadal, so his trademark forehand down the line is rarer every day.
In other words, the big 3 are actually not as good as before except on their serves (Djokovic now serves even slower than Federer), but how can they still beat the young guys, who serves much faster (first serve over 130 mph is the norm). There are many answers to this question. Firstly, tennis is a sport you can rest between points, games, and sets. So old guys can still recover. The winning strategy is to hold your serves, wait for opponents' mistakes, or focus on the key points in the tiebreaks. If you often get free service points, even better. Another reason is that coaching and big data analysis. The big 3, being so rich, likely can afford the best analyses and match preparations than most other players. Still, the young guys are clearly catching up, beating them many times already in 2019. So 2020 will be very interesting.
Then why can't badminton or table tennis players do this? Badminton may be more physically demanding than tennis, despite smaller courts and shorter match time. You have little designated time for rest during a match. You have to run, jump, turn, twist, even dive, so many times for a point. The intensity per unit of time is higher than in tennis. You are more likely to get penalized than to get a free point from your serves. Further, if you are tired for 5 min in badminton, you can kiss a set goodbye. Losing two sets, it is over. In tennis, 5 min likely only costs you a game; if it is his serving, matters even less.
How about table tennis, which is less demanding on the body? You can still get easy points on your serves, although harder than before. A limiting factor is that table tennis relies too much on reflexes and quickness, so simple biology, old guys just can't be as good as young no matter what. Old guys can compensate with experience and mentality, but high-ranking, younger players have that and improve on that as well.
In summary, top players (old and young) have similar skill levels, because there is no secret how they play, and everybody analyses everybody. But great players are just a bit better athletes: better reflexes, stamina, mentality, etc, so they dominate the sports longer. See "
Athleticism a key to elites’ success in sports". But once they get over 30, their advantages diminish, and little by little they are no longer better athletes. The uniqueness in tennis allows older players to persist, but other sports do not.
