As a serious old timer, I have watched such things happen regularly over the years. Sometimes, there is a certain something that makes a guy a tad better at one position than another. Or that two people working in tandem are greater then the individual parts when placed in the proper spots.
The Rams used that formula when drafting Fiske and Verse.
I have no idea if this involves "failure" or if when experimenting a better choice is discovered as concerns Avila and Jackson. But, I lean heavily towards a happy discovery rather than a failed expectation. It may well be that for the Rams Oline system, Jackson is even better at OC and Avila is even better at OG. I don't know. But I do know that McVay is probably a better judge of this than any of us.
As for the Jones thing, no doubt something happened. The Rams are closed mouth and just won't divulge things to irritate or denigrate a player. Something forced their hand. Anyone who has run anything that depends on human capital is familiar with this. Indeed, it may not be something the Rams wanted. On the other hand, the Rams FO doesn't look only at the current season, they look ahead 1 and 2 years. And, they don't seem to care much whether a guy is a 1st round pick or a UDFA. If a guy is the better player, he sticks and is ahead of the higher pick. And, for all we know, wherever they can save some cap for a reason we know nothing about could also play a role.
Bellicheck was famous for overweighting keeping the better players rather than just trying to fill out roster spots and depth with an NFL standard number of players. It seems the Rams have a bunch of good OLBs and Safeties. So, we see more of them kept around than typical depth for each position might be expected, as an example of this.
I find it interesting, too, their new philosophy at RB. They want a certain type that is plug and play with the guy ahead of him so the offense can stay the same if a starter or even his back-up goes down or needs a rest.
I've learned to sit back and relax, and let it all play out. Its a long season, and more goes on behind the scenes that in front of it.