apt install snapd tries to delete sysvinit-core:
apt install snapd
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following package was automatically installed and is no longer required:
linux-image-4.19.0-6-amd64
Use 'apt autoremove' to remove it.
The following additional packages will be installed:
dbus dbus-bin dbus-daemon dbus-session-bus-common dbus-system-bus-common dbus-user-session less
libblkid-dev libblkid1 libcryptsetup12 libdbus-1-3 libip4tc2 libjson-c5 libnss-systemd
libpam-systemd libseccomp2 libsystemd-dev libsystemd-shared libsystemd0 libudev-dev libudev1
squashfs-tools systemd systemd-sysv systemd-timesyncd udev
Suggested packages:
zenity | kdialog systemd-container systemd-homed systemd-userdbd systemd-boot systemd-resolved
libqrencode4 libtss2-esys-3.0.2-0 libtss2-mu0 libtss2-rc0 polkitd | policykit-1
The following packages will be REMOVED:
sysvinit-core
The following NEW packages will be installed:
dbus-bin dbus-daemon dbus-session-bus-common dbus-system-bus-common dbus-user-session libip4tc2
libjson-c5 libnss-systemd libpam-systemd libsystemd-shared snapd squashfs-tools systemd-sysv
systemd-timesyncd
The following packages will be upgraded:
dbus less libblkid-dev libblkid1 libcryptsetup12 libdbus-1-3 libseccomp2 libsystemd-dev
libsystemd0 libudev-dev libudev1 systemd udev
13 upgraded, 14 newly installed, 1 to remove and 1015 not upgraded.
Need to get 24.3 MB/24.4 MB of archives.
After this operation, 67.2 MB of additional disk space will be used.
Do you want to continue? [Y/n] n