Yes, its the money people who make the shots, the ones who bankrolled Skyrim Fallout 3 and Oblivion. They know that an quality product from an know franchise will sell well, they know Fallout 4 and TES 6 will outsell the previous game in the series.
In short had they been after short term profit they had launched new Fallout and TES games every second year Battlefield style, it could even work.
As for sub versus F2P, F2P in average bring in $3.8 month from customers over $10-15 for subscription, most F2P players are pretty causal and hardly use money.
However F2P get more players, and its easy to try the game. Now here is an major diference between Star Wars, Lord of the ring and TES, the two first has many hundred million fans, an free to play game will bring inn lots of people who are not hardcoe gamers, more in the candy crunch and angry bird league. Some of them will love the game and spend plenty of money.
For them F2P might well bring in more money.
TES has an magnitude less fans, around 25 millions, this is the target audience, yes you get more, you get people who are looking for an new MMO, but did not like single player Skyrim, plenty of PS4/ One player looking for any MMO or RPG. Still its an limited number, going F2P will not increase this number.
On the other hand you have idiotic greed, might be people living in their own fantasy world who believe you can combine Sub and P2W for more money, it might work, 2-3 months.
I have run my own company, first rule if you have an limited customer base: do not screw your customers hard. I was an independent software developer. Sometime customers was in an hurry, say an an bank had changed the interface so now the payment system was down and I needed to fix the webshop. Yes I could had demanded $10.000 for the work as they was down. I did not I billed them $1000 so they came back.
Yes the 1000 was still a ripoff for a couple hours work, but it was priority. On the other hand if your customers is tourist you want to rip the off hard as you never see them again.