So your actions alone can be valuable.
Your may inspire others or be part of a chain of things which inspires them.
Your hard won knowledge awaits their questions.
You may have to fight HOAs and disaproval. Your battles lay the groundwork for those that follow to succeed - setting precendent and raising issues, sometimes even by losing.
Even if others don't follow your practice you may pique their interest - which may change their opinions. Opinions are the mandate by which local officials and politicians act?
Many of these good consequences may be invisible to you. Doing good is never useless. The causes of change can be unpredictable and subtle. The future can be radically altered by small effects in the past.
Perhaps the life of a native bumble bee that survives by virtue of your planting may be the one that mutates enough so his descendants survive the coming changes.
Increase the luck surface for a good future.
Stay hopeful.