Right now Texas isn't putting Interstate highway shields on anything new unless it has something to do with the I-69 project. I would even count I-2 as part of the I-69 effort. Elsewhere in Texas many US and State highway segments have been built (or are in the process of being upgraded) to Interstate quality without getting an Interstate designation. That includes US-75/US-69 leading up to the Red River. I think some of this has to do with the amount of federal funding going into these projects. If the state of Texas has to pay for the bulk of the improvements why would they put an Interstate shield on the finished project?
If ODOT indeed requested US-69 be included in the Interstate highway system up to I-40 & Checotah that would make sense. I have long thought US-69 should be upgraded to Interstate quality from the Red River to Big Cabin & I-44.
Unfortunately it appears other people within Oklahoma are blocking improvements of the US-69 corridor, despite the ridiculous amounts of heavy truck traffic and dangers the current road design pose to motorists. According to what I've read elsewhere in this form people along the corridor in towns like Atoka and Stringtown have blocked corridor improvements, afraid their towns will die off if "bypassed." Never mind the fact small towns in Oklahoma are losing population to aging, youth migration to opportunties elsewhere and young people in general having far fewer children than past generations.
Oklahoma's state government is broke. The latest crisis is over teacher pay. Oklahoma now ranks dead freaking last in the nation. We've already been losing teachers, police officers, fire fighters, etc to better pay in other states. Years ago the state government passed big tax cuts it thought would create all sorts of growth that never happened. Its balanced budget law has forced the state to make deep cuts into the bone on many things, including public education. A recent measure to fund teacher pay raises with a fuel tax hike failed to pass. The state's fuel tax hasn't changed since 1993. IMHO fuel taxes should only be used to fund roads.
Some Interstate quality upgrades to US-69 are planned for Calera, McAlester and Muskogee. These will be useful upgrades, but far more has to be done to get the rest of the corridor upgraded. Changes in mindset need to happen in Oklahoma's state government and at the federal level.