Tyron Smith will also be around in practices to help coach up Tyler Smith. So Smith will get tutored by two future HOF left tackles. It could be worse.
I went back and read up on Tyler Smith's pre-draft evaluations. He was clearly OT4 on many lists, and considered a good late 1st round, early 2nd round prospect. Remember that 5-time Pro Bowl LT Flozell Adams was the 38th pick in the NFL draft in 1998. Tyler Smith may never be as good as Peters or Tyron Smith in their prime. But he has the tools to be a very good LT in the NFL, and getting tutored by two HOF players is a pretty good start to his career.
Let's face it. Cross is a rookie LT that will be starting in Seattle. It was probably inevitable that Tyler Smith was going to start at some point this season due to Tyron Smith's recent injury history. I think the Cowboys were pushing him at Left Guard to make sure he got on the field to get real world NFL experience in games, even as they waited for the likely injury of Tyron. That Tyron got injured in training camp, rather than later in the season may work to the Cowboys benefit.
Getting Tyron Smith back late in the season for a playoff run is not a bad option. Also, the Cowboys worked McGovern quite a lot at Center during training camp. We could conceivably be looking at a playoff Oline of LT Tyron Smith, LG Tyler Smith, C Connor McGovern, RG Zack Martin, and RT Jason Peters. With all the Cowboys in-season success, the important thing to most fans, and also the Jones family is translating that into playoff success, and getting to another Super Bowl. The Cowboys could stumble out of the gate with a 5-3 record - losing to the Buccaneers, Bengals and Rams, 3 of the last 4 Super Bowl contestants. But with the team getting healthier as the year progresses, and with the development of young players, they could go on a late season run and push into the playoffs in the best condition they've been in since 2014, when they had a team worthy of the Super Bowl.
I'm not making a prediction. But even if they experience a slow start, the Cowboys have set themselves up for late season strength and playoff success. That is the most you can ask of your front office. Now, it is up to the coaches and players to fulfill the promise.