I agree that Chen Meng's record against Ito is impressive and spotless, and she deserves high consideration for an Olympic Spot because of this. However, one must be cautious in giving too much weight to winning records and win streaks against certain players. In the Olympics, or any other major event where the pressure is great, win streaks and winning records may play less of a factor in determining the outcome.
A knock on Chen Meng's possible bid for an Olympic spot is that she's had winning records and streaks against several players in less prestigious events like the World Tour, but ends up losing to the same players in a much bigger event such as the World Championships or a Continental Title Event. 3 of such players are Liu Shiwen, Wang Manyu and Zhu Yuling.
Liu Shiwen- Chen Meng actually had a 6 match win streak against Liu from 2013 to 2019. Given this win streak, one would think that Chen Meng has a matchup and psychological advantage over Liu. However, in the 2019 WTTC final, the biggest stage, that win streak ended despite all signs pointing to Chen Meng continuing that win streak.
Wang Manyu- Chen Meng has won against her 9 of the last 10 times. The one time Chen Meng lost was in the final of the 2018 Asian Games, which China actually gives more weight to than any World Tour or Grand Final event.
Zhu Yuling- Chen Meng has won 6 out of the last 7 matches against her. The one time Chen Meng lost was in the final of the 2019 Asian Cup, which would have qualified her for the Women's World Cup. The Asian Cup is also a continental title event, which is a title Chen Meng still lacks, so it's strange that the only time Chen Meng has lost to Zhu in the last 7 matches was in this big event.
I think we should also take note of the fact that different national associations may value the same tournament differently. For example, there's a difference in how China values continental title events with how Japan values these same events. There's also a difference in the importance given by both China and Japan on the World Tour Grand Finals.
To illustrate:
Japan values the WTGF over Asian Title events. This is clear when they sent their "B-team" to the 2018 Asian Games, while its main players fought in the 2018 Bulgarian and Czech Opens to gain more rankings points and to earn more World Tour Standing points for the World Tour Grand Finals. In the 2019 Asian Championships, Japan didn't even send Ito to play or send Hayata to play in at least doubles. However, if you look at China's lineup, most, if not all the top players play in the continental title events.
China, on the other hand, values Asian Title events over the WTGF and World Tour events. There were times in the past where China didn't even send anyone to the WTGF because they didn't bother qualifying these players by sending them to play in enough World Tour events. Even today, there are times where China has no entries in doubles in the WTGF, so it's often we see other countries take the doubles titles in the WTGF. It's only because of the new WR system that pushes the CNT to play more events that we see more Chinese players qualify for the WTGF. In contrast, Japanese players usually join every World Tour event to try to qualify for the WTGF. In fact, Japan puts such a high weight in the WTGF that those players who qualified for the 2018 WTGF didn't have to go through the first screening of the 2019 WTTC selection tournament.
If Chen Meng's Olympic Bid was being evaluated using JTTA's criteria, she would be a lock for an Olympic singles spot given her wins on the World Tour and WTGF and her lack of continental titles would be brushed aside. However, using CTTA's criteria, where continental titles and majors are given much more importance, Chen Meng would be highly considered for an Olympic Singles spot, but that spot would be far from a sure thing.
In conclusion, I think that while Chen Meng is probably the player in the best form right now, the criticism she is receiving is still fair. No one is discounting what she has accomplished so far, or her spotless record against Ito. People are just concerned that in a major event, that winning record may not mean much given that she has a history of losing to players that she has had winning streaks against during bigger tournaments. This factor will be weighed against the shortcomings of the other women in the CNT.
In the end, all the CNT women have shortcomings that may make one think twice about choosing them for the Olympics. Chen Meng may not have proven herself enough in the biggest events despite winning many World Tour titles. Ding Ning has all the accolades and a history of performing well in the biggest events but is getting older and did lose badly to Ito last time. Sun Yingsha has already won several titles, including the Asian Championships, and even saved match points against Ito and Hirano in the biggest events of her life (Team World Cup and Youth Olympic Games), but some may still argue that she needs more experience before being selected. CTTA is in the best position to determine which among these shortcomings will least likely prevent China from winning 5 gold medals. CTTA is also in the best position to determine who among these players are in the best position to fix these shortcomings before the Olympics when they make their selection of the Olympic team. The CNT Road to Tokyo 2021 continues!