Ruby 2.6.6 weird behaviour for protected method

example.rb

class Item
  def initialize(value: )
    @value = value
  end

  def subitems
    @subitems ||= [
      Item.new(value: 1),
      Item.new(value: 2),
    ]
  end
    
  def aggregated_total1
    subitems.map{|i| i.value}.sum + value
  end

  def aggregated_total2
    subitems.map(&:value).sum + value
  end

  protected

  def value
    @value
  end
end

RUBY_DESCRIPTION # => "ruby 2.6.6p146 (2020-03-31 revision 67876) [x86_64-darwin19]"

Item.new(value: 0).aggregated_total1 # => 3
Item.new(value: 0).aggregated_total2 # NoMethodError: protected method `value' called for #<Item:0x00007fc5217b0258 @value=1>