Building Android: lunch warning about building a 32-bit-app-only product on a 64-bit device

Question

I'm trying to build Android, specifically /e/OS/ (based on lineageOS), for my device (ZTE Blade V2020 / Codename P671F60) following the official wiki. I synced the sources and set up a minimal device tree (see below).

When I run lunch lineage_P671F60-eng I get the following output:

build/make/core/board_config.mk:
Trying dependencies-only mode on a non-existing device tree?
build/make/core/board_config.mk:180: warning: Building a 32-bit-app-only product on a 64-bit device. If this is intentional, set TARGET_SUPPORTS_64_BIT_APPS := false

============================================
PLATFORM_VERSION_CODENAME=REL
PLATFORM_VERSION=10
TARGET_PRODUCT=lineage_P671F60
TARGET_BUILD_VARIANT=eng
TARGET_BUILD_TYPE=release
TARGET_ARCH=arm64
TARGET_ARCH_VARIANT=armv8-a
TARGET_CPU_VARIANT=generic
HOST_ARCH=x86_64
HOST_2ND_ARCH=x86
HOST_OS=linux
HOST_OS_EXTRA=Linux-6.5.7-artix1-1-x86_64-Artix-Linux
HOST_CROSS_OS=windows
HOST_CROSS_ARCH=x86
HOST_CROSS_2ND_ARCH=x86_64
HOST_BUILD_TYPE=release
BUILD_ID=QQ3A.200805.001
OUT_DIR=out
============================================

What does the warning warning: Building a 32-bit-app-only product on a 64-bit device. If this is intentional, set TARGET_SUPPORTS_64_BIT_APPS := false mean, did I cause this, and what problems could be caused by this?

---

My minimal device tree:

Android.mk:

LOCAL_PATH := $(call my-dir)

ifeq ($(TARGET_DEVICE),P671F60)
include $(call all-subdir-makefiles,$(LOCAL_PATH))
endif

AndroidProducts.mk

PRODUCT_MAKEFILES := \
    $(LOCAL_DIR)/lineage_P671F60.mk

COMMON_LUNCH_CHOICES := \
    lineage_P671F60-user \
    lineage_P671F60-userdebug \
    lineage_P671F60-eng

lineage_P671F60.mk:

PRODUCT_DEVICE := P671F60
PRODUCT_NAME := lineage_P671F60
PRODUCT_BRAND := ZTE
PRODUCT_MODEL := ZTE Blade V2020
PRODUCT_MANUFACTURER := ZTE

BoardConfig.mk:

DEVICE_PATH := device/ZTE/P671F60

# Architecture
TARGET_ARCH := arm64
TARGET_ARCH_VARIANT := armv8-a
TARGET_CPU_ABI := arm64-v8a
TARGET_CPU_ABI2 := 
TARGET_CPU_VARIANT := generic

# Bootloader
TARGET_BOOTLOADER_BOARD_NAME := peach
TARGET_NO_BOOTLOADER := true

# Platform
TARGET_BOARD_PLATFORM := mt6771
TARGET_BOARD_SUFFIX := _64