filterd_tracks.rb

def filtered_tracks(current_user)
  tracks = current_user.tracks.limit(500)
  rules = filters['rules']

  if rules.find {|h| h['id'] == 'track_name'}.present?
    track_name = rules.find {|h| h['id'] == 'track_name'}['value']

    tracks = tracks.where('tracks.name ILIKE ?', '%' + track_name + '%')
  end
  
  if rules.find {|h| h['id'] == 'artist_name'}.present?
    artist_name = rules.find {|h| h['id'] == 'artist_name'}['value']
    
    tracks = tracks.joins(:artist).where('artists.name ILIKE ?', '%' + artist_name + '%')
  end

  tracks
end

You could also consider extracting a method like:

def find_rule(rules, rule_name)
  rules.find{|r| r['id'] == rule_name}
end

if you don't want to keep typing r["id"] == "blah"

def filtered_tracks(current_user)
  tracks = current_user.tracks.limit(500)
  rules = filters['rules']

  find_rule(rules, 'track_name').try do |rule|
    tracks = tracks.where('tracks.name ILIKE ?', '%' + rule['value'] + '%')
  end
  
  find_rule(rules, 'artist_name').try do |rule|
    tracks = tracks.joins(:artist).where('artists.name ILIKE ?', '%' + rule['value'] + '%')
  end

  tracks
end

def find_rule(rules, rule_name)
  rules.find{|r| r['id'] == rule_name}
end