Switch will sell more lifetime. I see PS5 selling less than PS4, while Xbox Series X|S selling a bit better than the Xbox One. Right now the Switch is tracking ahead of the PS4 despite having one less holiday.
VGChartz sales comparison article on Switch vs PS4:
Switch Vs. PS4 Global:
Gap change in latest month: 464,164 - Switch
Gap change over last 12 months: 7,320,053 - Switch
Total Lead: 4,838,114 - Switch
Switch Total Sales: 63,403,962
PS4 Total Sales: 58,565,848
August 2020 is the 42nd month that the Nintendo Switch has been available for. During the latest month, the gap grew in favor of the Switch by 464,164 units when compared to the PlayStation 4 during the same timeframe. In the last 12 months, the Switch has outsold the PlayStation 4 by 7.32 million units. The Switch is currently ahead of the PlayStation 4 by 4.84 million units.
The PlayStation 4 launched in November 2013, while the Nintendo Switch launched worldwide in March 2017. Therefore, the holiday periods for the two consoles do not lineup, which is why there are big increases and decreases.
The 42nd month on sale for the Nintendo Switch is August 2020, while for the PlayStation 4 it is April 2017. The Switch has sold 623.40 million units, while the PlayStation 4 sold 58.57 million units during the same timeframe. The PlayStation 4 did not reach current Switch sales until month 47.
The PlayStation 4 has sold 112.96 million units through August 2020. The Nintendo Switch is currently 49.56 million units behind the lifetime sales of the PlayStation 4.