I agree about Foundry being a bit daunting when you first start. However for those that have started on Roll20 and have gotten into the idea of VTT and how it is suppose to work, crossing over isn't too much of a problem. There are a lot of YouTube videos out there to help new people and there is also a support board and Discord board.
I think that Roll20 really has seen its hay day and more and more players are converting over to Foundry. I can't code a bit but I know there are those out there that can and it would be nice if those in the community that could would develop content for it.
On the the other hand I don't see ICE doing much to help its self in this regard. Most of the pushing if not all is being done by it's fan base.
As for me, I'm tired of waiting on the new RMU. I'm satisfied with RMSS "what we play with". I just wish they would open it up for developers for new content modules. I've been playing for over 30 years heck since it first came out and have content for my group but I can't do anything with it as far as putting it out there for others.
For example;
Look at "Rolemaster Combat minion" a online aide which I use and depend on every other week in my game. It is a great helper and does all the heavy lifting in combat, even keeping track of all the HP, bloodloss per round, and stuns and applying crits which it looks up. The guy who developed it has been begging someone to take it over, I've seen his posts here on the board. As far as I know ICE had not done anything to help or to offer to take it over. It would only benefit them in the long run if they would because it takes a part of the game which is daunting for some people and makes it all instantaneous so play continues to run smoothly. If it goes down I'm back to having to chart look and to keeping track of everything for combat by hand. Heck the system is so nice it even keeps a record of your combat session that you can look at and review.
Sorry a bit off the topic and rambly.