Just some other Square Enix games on the Switch
Dragon Quest Builders 2 Launch vs Lifetime Sales
Dragon Quest Builders 2 - 97.673
Dragon Quest Builders 2 - 290.255
Octopath Traveler Launch vs Lifetime Sales
Octopath Traveler - 109.579
Octopath Traveler - 193.780
Dragon Quest XI S Launch vs Lifetime Sales
Dragon Quest XI S - 303.204
Dragon Quest XI S – 518.979
Trials of Mana - 70.114
Only Octopath Traveller faced similar shortages at launch to Trials of Mana and still nearly doubled its sales.
So I wouldn't rule out that by next year the Switch version outselling the PS4 version. The Switch is set to have a record-breaking year in Japan, we are talking at least 3M more hardware sold by the end of the year. So even a game like Trials of Mana will benefit. When Famitsu releases their Top 100 for 2020 we will see which one ends up on top.
But the original argument was regarding shortages, and yes Trials of Mana continue to have shortages on the Switch in Japan(for example it's out of stock on Amazon, while there the PS4 version is in stock). Demand has not been met & with the second-hand market Square Enix missed some sales in Japan.
Luckily they will make up these Sales elsewhere, for example Trials of Mana was in the top 10 for April in the NPD Switch Ranking. This was during a month where Switch sold 800K in North America. So despite missing sales in Japan Square did provide enough stock elsewhere for the game to do respectfully well. I won't be surprised to see it sell over 1M on the Switch World Wide by the end of the year which would continue to ensure similar AA are launched on the Switch in the future.