> Isn't the primary reason why games don't get release to avoid them competing with modern games for gamers focus.
Games companies are constantly and ruthlessly competing with each other for gamer focus over modern games. You don't avoid that competition by simply not releasing your own stuff.
But even assuming you still have the original source code and assets for a title, spending a good chunk of $$$ to modernize a title to run decently on modern operating systems (lest you be flooded with time/$$$ consuming support requests), updating assets to to look like they're from the current decade (so it's marketable beyond an extremely niche nostalgic audience), all to maybe get a fraction of the original sales when second hand sales and piracy have likely saturated the market for the original, as sought out by the nostalgic - it's simply not a great time investment.
You can drive down the costs by just throwing DOSBox at the problem in some cases, like GOG has done for many titles. Or maybe it's been so long that your remaster is effectively a new game, ala FF7, and you can sell it to a whole new generation of gamers. Or maybe you had a subscription based game ala WOW, and maybe third party reverse engineered servers didn't already completely moot the interest in a re-release. Maybe.
But even then, a re-release is probably not going to be your next genre-defining blockbuster title.