Yes. The channel that I need the second antenna for still came in solidly, but all the other channels that the first antenna picks up stopped coming in solidly. That was with an ordinary splitter. They also make ones that look like splitters but are labeled as "combiners" or "splitter/combiners," like this:

https://www.amazon.com/ChannelPlus-2512-channelplus-splitter-combiner/dp/B07C55K25K

I don't have one of those to try and I don't know what's going on inside them that makes them different than a regular splitter, but if it would work as well as manually switching between the two antennas then that would be ideal. However, reviews of various combiners that I've read make me think they probably won't work for me, like this one:

First, the good news: this unit works beautifully to combine signals from two antennas, IF you observe a few simple rules.

First, attach both antennas to the same mast, so they are separated vertically by at least 4 feet. It helps if your antennas don't overlap too much in their reception patterns.

Next, cut a coaxial cable to traverse the distance from the upper antenna to your antenna combiner. Cut a second cable to exactly the same length as this cable. Alternatively, you can use pre-manufactured cables, but make sure they are exactly the same length. This part is critical.

Now use these two cables to connect your two antennas to the combiner.

Failure to use feed lines from the two antennas of exactly the same length will cause the signal from the same station to arrive at the combiner box twice, separated by a short duration in time between them (about 1 nanosecond per foot of differing length). This can cause both signal cancellation and signal lock problems due to multi-path interference.

So get those cables exactly right! You can loosely coil up the excess cable coming from the closer antenna.

My setup doesn't even come close to what he's talking about. I have a traditional Yagi-type VHF roof antenna at the back of the house which receives most of my channels, and then for the channel that I can hardly ever receive through the roof antenna, I use a simple folded dipole antenna at the front of the house that I made from 300 ohm twin-lead, which reliably receives that channel.