Should an OOP developer only seek companies in tune with their desired direction and abilities?
If you really want to do OOP work, you probably need to change jobs. There could well come a time that your employer is not so thrilled with you using company time to stay fresh on OOP when it doesn't serve the company agenda.
Look at a switch to OOP from your employer perspective for a minute. Are you the only developer? Then you might be able to get a change in programming model accomplished. If there's a number of other developers, the organization has momentum that is difficult to turn. Those other developers would also need to change models and may not have the skills so now it's also a big training and re-staffing issue.
If your boss is not aware what object orientated programming is then that should be a massive red flag for the software shop.
If you are afraid that your skillset will atrophy unless you do at least 8 hours a day of practice then that should be a massive red flag for you as a developer, I have not written any code in Visual Studio for windows in over 10 years, but if I have to I am sure that I can hop back into it and hit 90% productivity in a matter of hours.
Unless the core product of said company is software components (so their main customer base is programmers) then there is no reason or indication as to why there is a need for a dramatic change, due to the fact that 100% of customers dont actually
(in my experience complete re-writes of projects tend to repeat all the same mistakes as the original software. )